introduction to character tables the character table for c...

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Outline

1 Introduction to Character Tables

2 The Character Table for C2v

3 The Character Table for C3v

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Quote from Eugene Paul WignerSee also: Current Science, vol. 69, no. 4, 25 August 1995, p. 375

From the preface to his book on group theory:

Wigner relates a conversation with von Laue on the use of grouptheory as the natural tool with which to tackle problems inquantum mechanics. “I like to recall his question as to whichresults... I considered most important. My answer was that theexplanation of Laporte’s rule (the concept of parity) and thequantum theory of the vector addition model appeared to me mostsignificant. Since that time, I have come to agree with his answerthat the recognition that almost all rules of spectroscopy followfrom the symmetry of the problem is the most remarkable result.”

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

What Makes Up a Character TableCharacter tables contain information about how functions transform in response to theoperations of the group

Five parts of a character table

1 At the upper left is the symbol for the point group

2 The top row shows the operations of the point group,organized into classes

3 The left column gives the Mulliken symbols for each of theirreducible representations

4 The rows at the center of the table give the characters of theirreducible representations

5 Listed at right are certain functions, showing the irreduciblerepresentation for which the function can serve as a basis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

What Makes Up a Character TableCharacter tables contain information about how functions transform in response to theoperations of the group

Five parts of a character table

1 At the upper left is the symbol for the point group

2 The top row shows the operations of the point group,organized into classes

3 The left column gives the Mulliken symbols for each of theirreducible representations

4 The rows at the center of the table give the characters of theirreducible representations

5 Listed at right are certain functions, showing the irreduciblerepresentation for which the function can serve as a basis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

What Makes Up a Character TableCharacter tables contain information about how functions transform in response to theoperations of the group

Five parts of a character table

1 At the upper left is the symbol for the point group

2 The top row shows the operations of the point group,organized into classes

3 The left column gives the Mulliken symbols for each of theirreducible representations

4 The rows at the center of the table give the characters of theirreducible representations

5 Listed at right are certain functions, showing the irreduciblerepresentation for which the function can serve as a basis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

What Makes Up a Character TableCharacter tables contain information about how functions transform in response to theoperations of the group

Five parts of a character table

1 At the upper left is the symbol for the point group

2 The top row shows the operations of the point group,organized into classes

3 The left column gives the Mulliken symbols for each of theirreducible representations

4 The rows at the center of the table give the characters of theirreducible representations

5 Listed at right are certain functions, showing the irreduciblerepresentation for which the function can serve as a basis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

What Makes Up a Character TableCharacter tables contain information about how functions transform in response to theoperations of the group

Five parts of a character table

1 At the upper left is the symbol for the point group

2 The top row shows the operations of the point group,organized into classes

3 The left column gives the Mulliken symbols for each of theirreducible representations

4 The rows at the center of the table give the characters of theirreducible representations

5 Listed at right are certain functions, showing the irreduciblerepresentation for which the function can serve as a basis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C2v Character Table

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vWhat happens when the E operation is applied?

The E operation is a rotation by 360◦ about an arbitrary axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vWhat happens when the E operation is applied?

The E operation is a rotation by 360◦ about an arbitrary axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vThe E operation returns the original configuration of the s orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vThe E operation returns the original configuration of the s orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vWhat happens when the C2 operation is applied?

The C2 operation is a rotation by 180◦ about the z axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vWhat happens when the C2 operation is applied?

The C2 operation is a rotation by 180◦ about the z axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vThe C2 operation returns the original configuration of the s orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vThe C2 operation returns the original configuration of the s orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vWhat happens when the σv (xz) operation is applied?

The σv (xz) operation is a reflection through the xz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vWhat happens when the σv (xz) operation is applied?

The σv (xz) operation is a reflection through the xz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vThe σv (xz) operation returns the original configuration of the s orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vThe σv (xz) operation returns the original configuration of the s orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vWhat happens when the σ′

v (yz) operation is applied?

The σ′v (yz) operation is a reflection through the yz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vWhat happens when the σ′

v (yz) operation is applied?

The σ′v (yz) operation is a reflection through the yz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vThe σ′

v (yz) operation returns the original configuration of the s orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s Orbital in C2vThe σ′

v (yz) operation returns the original configuration of the s orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s OrbitalThese observations pertain to any central-atom s orbital in any point group

Consider an s orbital located on a central atom

An example of a central atom is O in the case of water, or Nin the case of ammonia

Carrying out any operation on a central atom s orbital returnsthe s orbital in its original configuration

The central-atom s orbital “belongs to” or “serves as a basisfor” the totally symmetric (A1) irreducible representation

All the characters of the totally symmetric irreduciblerepresentation are 1

The totally symmetric irreducible representation is alwayssingly degenerate

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s OrbitalThese observations pertain to any central-atom s orbital in any point group

Consider an s orbital located on a central atom

An example of a central atom is O in the case of water, or Nin the case of ammonia

Carrying out any operation on a central atom s orbital returnsthe s orbital in its original configuration

The central-atom s orbital “belongs to” or “serves as a basisfor” the totally symmetric (A1) irreducible representation

All the characters of the totally symmetric irreduciblerepresentation are 1

The totally symmetric irreducible representation is alwayssingly degenerate

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s OrbitalThese observations pertain to any central-atom s orbital in any point group

Consider an s orbital located on a central atom

An example of a central atom is O in the case of water, or Nin the case of ammonia

Carrying out any operation on a central atom s orbital returnsthe s orbital in its original configuration

The central-atom s orbital “belongs to” or “serves as a basisfor” the totally symmetric (A1) irreducible representation

All the characters of the totally symmetric irreduciblerepresentation are 1

The totally symmetric irreducible representation is alwayssingly degenerate

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s OrbitalThese observations pertain to any central-atom s orbital in any point group

Consider an s orbital located on a central atom

An example of a central atom is O in the case of water, or Nin the case of ammonia

Carrying out any operation on a central atom s orbital returnsthe s orbital in its original configuration

The central-atom s orbital “belongs to” or “serves as a basisfor” the totally symmetric (A1) irreducible representation

All the characters of the totally symmetric irreduciblerepresentation are 1

The totally symmetric irreducible representation is alwayssingly degenerate

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s OrbitalThese observations pertain to any central-atom s orbital in any point group

Consider an s orbital located on a central atom

An example of a central atom is O in the case of water, or Nin the case of ammonia

Carrying out any operation on a central atom s orbital returnsthe s orbital in its original configuration

The central-atom s orbital “belongs to” or “serves as a basisfor” the totally symmetric (A1) irreducible representation

All the characters of the totally symmetric irreduciblerepresentation are 1

The totally symmetric irreducible representation is alwayssingly degenerate

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of an s OrbitalThese observations pertain to any central-atom s orbital in any point group

Consider an s orbital located on a central atom

An example of a central atom is O in the case of water, or Nin the case of ammonia

Carrying out any operation on a central atom s orbital returnsthe s orbital in its original configuration

The central-atom s orbital “belongs to” or “serves as a basisfor” the totally symmetric (A1) irreducible representation

All the characters of the totally symmetric irreduciblerepresentation are 1

The totally symmetric irreducible representation is alwayssingly degenerate

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vWhat happens when the E operation is applied?

The E operation is a rotation by 360◦ about an arbitrary axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vWhat happens when the E operation is applied?

The E operation is a rotation by 360◦ about an arbitrary axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vThe E operation returns the original configuration of the px orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vThe E operation returns the original configuration of the px orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vWhat happens when the C2 operation is applied?

The C2 operation is a rotation by 180◦ about the z axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vWhat happens when the C2 operation is applied?

The C2 operation is a rotation by 180◦ about the z axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vThe C2 operation inverts the phase of the px orbital

The result of this corresponds to a character of −1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vThe C2 operation inverts the phase of the px orbital

The result of this corresponds to a character of −1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vWhat happens when the σv (xz) operation is applied?

The σv (xz) operation is a reflection through the xz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vWhat happens when the σv (xz) operation is applied?

The σv (xz) operation is a reflection through the xz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vThe σv (xz) operation does nothing to the phase of the px orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vThe σv (xz) operation does nothing to the phase of the px orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vWhat happens when the σ′

v (yz) operation is applied?

The σ′v (yz) operation is a reflection through the yz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vWhat happens when the σ′

v (yz) operation is applied?

The σ′v (yz) operation is a reflection through the yz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vThe σ′

v (yz) operation inverts the phase of the px orbital

The result of this corresponds to a character of −1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a px Orbital in C2vThe σ′

v (yz) operation inverts the phase of the px orbital

The result of this corresponds to a character of −1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

A px Orbital has B1 Symmetry in C2v

We carried out the operations of C2v on a central-atom pxorbital

This generated the following row of characters: 1,−1, 1,−1

This row of characters in the C2v character table is labeled B1

Any orbital having these transformation properties in C2v issaid to have B1 symmetry

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

A px Orbital has B1 Symmetry in C2v

We carried out the operations of C2v on a central-atom pxorbital

This generated the following row of characters: 1,−1, 1,−1

This row of characters in the C2v character table is labeled B1

Any orbital having these transformation properties in C2v issaid to have B1 symmetry

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

A px Orbital has B1 Symmetry in C2v

We carried out the operations of C2v on a central-atom pxorbital

This generated the following row of characters: 1,−1, 1,−1

This row of characters in the C2v character table is labeled B1

Any orbital having these transformation properties in C2v issaid to have B1 symmetry

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

A px Orbital has B1 Symmetry in C2v

We carried out the operations of C2v on a central-atom pxorbital

This generated the following row of characters: 1,−1, 1,−1

This row of characters in the C2v character table is labeled B1

Any orbital having these transformation properties in C2v issaid to have B1 symmetry

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vWhat happens when the E operation is applied?

The E operation is a rotation by 360◦ about an arbitrary axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vWhat happens when the E operation is applied?

The E operation is a rotation by 360◦ about an arbitrary axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vThe E operation returns the original configuration of the py orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vThe E operation returns the original configuration of the py orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vWhat happens when the C2 operation is applied?

The C2 operation is a rotation by 180◦ about the z axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vWhat happens when the C2 operation is applied?

The C2 operation is a rotation by 180◦ about the z axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vThe C2 operation inverts the phase of the py orbital

The result of this corresponds to a character of −1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vThe C2 operation inverts the phase of the py orbital

The result of this corresponds to a character of −1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vWhat happens when the σv (xz) operation is applied?

The σv (xz) operation is a reflection through the xz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vWhat happens when the σv (xz) operation is applied?

The σv (xz) operation is a reflection through the xz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vThe σv (xz) operation inverts the phase of the py orbital

The result of this corresponds to a character of −1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vThe σv (xz) operation inverts the phase of the py orbital

The result of this corresponds to a character of −1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vWhat happens when the σ′

v (yz) operation is applied?

The σ′v (yz) operation is a reflection through the yz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vWhat happens when the σ′

v (yz) operation is applied?

The σ′v (yz) operation is a reflection through the yz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vThe σ′

v (yz) operation does nothing to the phase of the py orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a py Orbital in C2vThe σ′

v (yz) operation does nothing to the phase of the py orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

A py Orbital has B2 Symmetry in C2v

We carried out the operations of C2v on a central-atom pyorbital

This generated the following row of characters: 1,−1,−1, 1

This row of characters in the C2v character table is labeled B2

Any orbital having these transformation properties in C2v issaid to have B2 symmetry

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

A py Orbital has B2 Symmetry in C2v

We carried out the operations of C2v on a central-atom pyorbital

This generated the following row of characters: 1,−1,−1, 1

This row of characters in the C2v character table is labeled B2

Any orbital having these transformation properties in C2v issaid to have B2 symmetry

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

A py Orbital has B2 Symmetry in C2v

We carried out the operations of C2v on a central-atom pyorbital

This generated the following row of characters: 1,−1,−1, 1

This row of characters in the C2v character table is labeled B2

Any orbital having these transformation properties in C2v issaid to have B2 symmetry

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

A py Orbital has B2 Symmetry in C2v

We carried out the operations of C2v on a central-atom pyorbital

This generated the following row of characters: 1,−1,−1, 1

This row of characters in the C2v character table is labeled B2

Any orbital having these transformation properties in C2v issaid to have B2 symmetry

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vWhat happens when the E operation is applied?

The E operation is a rotation by 360◦ about an arbitrary axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vWhat happens when the E operation is applied?

The E operation is a rotation by 360◦ about an arbitrary axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vThe E operation returns the original configuration of the pz orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vThe E operation returns the original configuration of the pz orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vWhat happens when the C2 operation is applied?

The C2 operation is a rotation by 180◦ about the z axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vWhat happens when the C2 operation is applied?

The C2 operation is a rotation by 180◦ about the z axis

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vThe C2 operation does nothing to the phase of the pz orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vThe C2 operation does nothing to the phase of the pz orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vWhat happens when the σv (xz) operation is applied?

The σv (xz) operation is a reflection through the xz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vWhat happens when the σv (xz) operation is applied?

The σv (xz) operation is a reflection through the xz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vThe σv (xz) operation inverts the phase of the pz orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vThe σv (xz) operation inverts the phase of the pz orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vWhat happens when the σ′

v (yz) operation is applied?

The σ′v (yz) operation is a reflection through the yz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vWhat happens when the σ′

v (yz) operation is applied?

The σ′v (yz) operation is a reflection through the yz plane

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vThe σ′

v (yz) operation does nothing to the phase of the pz orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Transformation Properties of a pz Orbital in C2vThe σ′

v (yz) operation does nothing to the phase of the pz orbital

The result of this corresponds to a character of 1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

A pz Orbital has A1 Symmetry in C2v

We carried out the operations of C2v on a central-atom pzorbital

This generated the following row of characters: 1, 1, 1, 1

This row of characters in the C2v character table is labeled A1

Any orbital having these transformation properties in C2v issaid to have A1 symmetry

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

A pz Orbital has A1 Symmetry in C2v

We carried out the operations of C2v on a central-atom pzorbital

This generated the following row of characters: 1, 1, 1, 1

This row of characters in the C2v character table is labeled A1

Any orbital having these transformation properties in C2v issaid to have A1 symmetry

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

A pz Orbital has A1 Symmetry in C2v

We carried out the operations of C2v on a central-atom pzorbital

This generated the following row of characters: 1, 1, 1, 1

This row of characters in the C2v character table is labeled A1

Any orbital having these transformation properties in C2v issaid to have A1 symmetry

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

A pz Orbital has A1 Symmetry in C2v

We carried out the operations of C2v on a central-atom pzorbital

This generated the following row of characters: 1, 1, 1, 1

This row of characters in the C2v character table is labeled A1

Any orbital having these transformation properties in C2v issaid to have A1 symmetry

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Symmetry Restrictions on Molecular Orbitals (MOs)

Only orbitals of the same symmetry may mix

“Orbitals of the same symmetry” belong to the sameirreducible representation

For the C2v water molecule, the oxygen s and pz atomicorbitals may contribute to any molecular orbital of A1

symmetry, but px and py may not

Any valid molecular orbital must transform according to oneof the irreducible representations of the molecular point group

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Symmetry Restrictions on Molecular Orbitals (MOs)

Only orbitals of the same symmetry may mix

“Orbitals of the same symmetry” belong to the sameirreducible representation

For the C2v water molecule, the oxygen s and pz atomicorbitals may contribute to any molecular orbital of A1

symmetry, but px and py may not

Any valid molecular orbital must transform according to oneof the irreducible representations of the molecular point group

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Symmetry Restrictions on Molecular Orbitals (MOs)

Only orbitals of the same symmetry may mix

“Orbitals of the same symmetry” belong to the sameirreducible representation

For the C2v water molecule, the oxygen s and pz atomicorbitals may contribute to any molecular orbital of A1

symmetry, but px and py may not

Any valid molecular orbital must transform according to oneof the irreducible representations of the molecular point group

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Symmetry Restrictions on Molecular Orbitals (MOs)

Only orbitals of the same symmetry may mix

“Orbitals of the same symmetry” belong to the sameirreducible representation

For the C2v water molecule, the oxygen s and pz atomicorbitals may contribute to any molecular orbital of A1

symmetry, but px and py may not

Any valid molecular orbital must transform according to oneof the irreducible representations of the molecular point group

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C2v Character Table

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The Molecular Orbitals of Water

Notice that the water HOMO is a pure oxygen px orbital ofB1 symmetry

The hydrogen atoms with their 1s valence orbitals lie in thenodal plane of the oxygen px orbital

The two hydrogen 1s orbitals give rise to linear combinationsof A1 and B2 symmetry

The O-H bonding molecular orbitals must likewise be of A1

and B2 symmetry

Given that all the irreducible representations of C2v are singlydegenerate, so must be all the MOs of the water molecule

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The Molecular Orbitals of Water

Notice that the water HOMO is a pure oxygen px orbital ofB1 symmetry

The hydrogen atoms with their 1s valence orbitals lie in thenodal plane of the oxygen px orbital

The two hydrogen 1s orbitals give rise to linear combinationsof A1 and B2 symmetry

The O-H bonding molecular orbitals must likewise be of A1

and B2 symmetry

Given that all the irreducible representations of C2v are singlydegenerate, so must be all the MOs of the water molecule

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The Molecular Orbitals of Water

Notice that the water HOMO is a pure oxygen px orbital ofB1 symmetry

The hydrogen atoms with their 1s valence orbitals lie in thenodal plane of the oxygen px orbital

The two hydrogen 1s orbitals give rise to linear combinationsof A1 and B2 symmetry

The O-H bonding molecular orbitals must likewise be of A1

and B2 symmetry

Given that all the irreducible representations of C2v are singlydegenerate, so must be all the MOs of the water molecule

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The Molecular Orbitals of Water

Notice that the water HOMO is a pure oxygen px orbital ofB1 symmetry

The hydrogen atoms with their 1s valence orbitals lie in thenodal plane of the oxygen px orbital

The two hydrogen 1s orbitals give rise to linear combinationsof A1 and B2 symmetry

The O-H bonding molecular orbitals must likewise be of A1

and B2 symmetry

Given that all the irreducible representations of C2v are singlydegenerate, so must be all the MOs of the water molecule

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The Molecular Orbitals of Water

Notice that the water HOMO is a pure oxygen px orbital ofB1 symmetry

The hydrogen atoms with their 1s valence orbitals lie in thenodal plane of the oxygen px orbital

The two hydrogen 1s orbitals give rise to linear combinationsof A1 and B2 symmetry

The O-H bonding molecular orbitals must likewise be of A1

and B2 symmetry

Given that all the irreducible representations of C2v are singlydegenerate, so must be all the MOs of the water molecule

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C3v Character Table

Note that the E irreducible representation begins with a 2

This means that orbitals of E symmetry in C3v are doublydegenerate

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C3v Character Table

Note that the E irreducible representation begins with a 2

This means that orbitals of E symmetry in C3v are doublydegenerate

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C3v Character Table

Note that the E irreducible representation begins with a 2

This means that orbitals of E symmetry in C3v are doublydegenerate

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C3v Character Table

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C3v Character Table

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C3v Character Table: Definition of “Character”

a character is the trace of a matrix

that means the sum of its diagonal elements

physically, it means the amount of the original functionremaining after the operation

here, C3 on (x , y) gives a character of −12 − 1

2 = −1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C3v Character Table: Definition of “Character”

a character is the trace of a matrix

that means the sum of its diagonal elements

physically, it means the amount of the original functionremaining after the operation

here, C3 on (x , y) gives a character of −12 − 1

2 = −1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C3v Character Table: Definition of “Character”

a character is the trace of a matrix

that means the sum of its diagonal elements

physically, it means the amount of the original functionremaining after the operation

here, C3 on (x , y) gives a character of −12 − 1

2 = −1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C3v Character Table: Definition of “Character”

a character is the trace of a matrix

that means the sum of its diagonal elements

physically, it means the amount of the original functionremaining after the operation

here, C3 on (x , y) gives a character of −12 − 1

2 = −1

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C3v Character Table

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C3v Character Table

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The C3v Character Table

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

The Oh Character Table

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Molecular Orbital Diagram for Ammonia, NH3

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

Highest Occupied MO of Ammonia, NH3

5.03 Inorganic Chemistry

Introduction to Character TablesThe Character Table for C2vThe Character Table for C3v

E Symmetry Bonding MO of Ammonia, NH3

5.03 Inorganic Chemistry