chapter 1: soft condensed matter
DESCRIPTION
Introductory presentation about soft condensed matterTRANSCRIPT
![Page 1: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/1.jpg)
Ivan I. Smalyukh
Soft Condensed Matter Physics
Department of Physics &
Liquid Crystals Materials Research Center
University of Colorado at Boulder
http://www.colorado.edu/physics/SmalyukhLab/SoftMatter/
![Page 2: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/2.jpg)
Soft Condensed Matter Physics "Soft Condensed Matter Physics " is a course about
the science of liquid crystals, polymers, plastic crystals, biological membranes, biopolymers, block copolymers, molecular monolayers, colloids, nanoparicle suspensions, emulsions, foams, gels, elastomers, ferrofluids, granular materials, cells, tissues, filamentous networks, electro-rheological fluids, paints, foods, inks, cosmetics and other soft materials.
Is there something in common between these very different soft matter systems? 2
![Page 3: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/3.jpg)
3
Pierre-Gilles de Gennes (Nobel prize in physics 1991): ”All physicochemical systems that have large response functions.”(i.e., a mild external influence has a big effect) Helmut Möhwald (Editorial board member, Soft Matter): ”Materials that are held together by non-covalent interactions. These interactions are typically weak, often on the order of kT and thus comparable to entropic forces.”
Richard A. L. Jones, in Soft Condensed Matter: ”Materials in states of matter that are neither simple liquids nor crystalline solids of the type studied in other branches of solid state physics.”
Before tackling actual complex soft matter systems, we need to understand (amongst other things) these response functions, non-covalent interactions and entropic forces.
What do we mean by Soft Condensed Matter?
![Page 4: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/4.jpg)
• The term usually refers to states of matter which are neither simple liquids nor crystalline solids.
• Includes many familiar types of matter – soap, yoghurt, paint, liquid crystals, putty….but also much of our bodies including cell membranes and the cytoplasm inside.
• In general we will be dealing with lengthscales intermediate between atomic and macroscopic; these are often known as mesoscopic.
• Quantum mechanics will not therefore be very useful; the predominant techniques we will use will be statistical.
• Mean field theories will be found to be useful, as you have seen before, to describe the behaviour of large numbers of molecules.
• Although dealing with ensembles of molecules, we will find that thermal energy is comparable with the energies giving rise to distortion and interaction energies, so Brownian motion and fluctuations are important.
• This is a key difference with 'hard condensed matter' for which thermal fluctuations are not important.
What do we mean by Soft Condensed Matter?
![Page 5: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/5.jpg)
![Page 6: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/6.jpg)
6
![Page 7: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/7.jpg)
Liquid Crystals (LCs)
n̂
Average local molecular orientations in liquid crystals are described by the director with head-tail symmetry nn ˆˆ −≡
Crystal liquid crystal Isotropic fluid
→ Flow like liquids; → Anisotropic like solid crystals; CN
![Page 8: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/8.jpg)
Nematic liquid crystal
n
director
![Page 9: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/9.jpg)
n
director
Only orientational order (crystal), no positional order (liquid)
center of mass locations
Nematic liquid crystal
![Page 10: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/10.jpg)
10
Very useful soft materials → Response to tiny external fields
J. Hwang et al., Nature materials 4, 383 (2005)
→ Periodic structure of molecular orientations with a defect layer.
→ Learning from nature: soft materials are useful for a variety of applications;
Fujicake, Sato, & Murashige, Tokyo, Japan.
→ Flexible displays
~E
kHzf 1~
Vvoltage 1~
![Page 11: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/11.jpg)
Flat Panel LCD TVs – just an example
![Page 12: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/12.jpg)
12
Plastic Crystals – no orientational order
![Page 13: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/13.jpg)
13
![Page 14: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/14.jpg)
Colloids • Colloids are systems in which one of the systems (at least) has dimensions
of ~1µm or less. • Thus many aspects of nanotechnology are essentially colloidal.
• Examples: Solid in liquid such as Indian
Ink or sunscreen Suspension Liquid in Liquid such as
mayonnaise or salad dressing Emulsion Gas in Liquid such as beer or
soap foam Foam
Gas in Solid such as bath sponge or ice cream
Sponge
![Page 15: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/15.jpg)
15
![Page 16: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/16.jpg)
![Page 17: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/17.jpg)
Semi-flexible biopolymers
2 – 30 micron length 7-8 nm in diameter
~ 16 micron persistence length
Actin Wormlike Micelle ( polybutadiene-polyethyleneoxide )
10 – 50 micron length ~ 15 nm in diameter
~ 500 nm persistence length
DNA
16 micron length 2 nm in diameter
40 nm persistence length
Neurofilament
5 - 20 micron length 12 nm in diameter
~ 220 nm persistence length
![Page 18: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/18.jpg)
18
![Page 19: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/19.jpg)
![Page 20: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/20.jpg)
20
![Page 21: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/21.jpg)
21
(1) Interactions / Forces • What are the interactions between constituents? • How do these interactions arise? • How do these interactions affect self-assembly, structure, dynamics, rheology, transport properties? (2) Self-Assembly / Collective Properties • Novel Phases (Equilibrium Statistical Physics) • Role of shape, charge, concentration, conformation, size, ... • Structure, Dynamics, Rheology, Optical Properties, ... • Beyond Equilibrium: Metastable phases, glasses, …
We are interested in understanding
![Page 22: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/22.jpg)
22
• Soft Matter is susceptible to small external influences (”large response functions”) • Has a complex microscopic structure, composition and internal dynamics • Means such systems as colloids, polymers, liquid crystals,
surfactants, and biological matter
• Exhibits a huge range of different time and length scales
• Usually Entropy Dominates! (But not quantum mechanics!)
Unifying properties of soft matter
![Page 23: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/23.jpg)
23
Useful Books (1) P.M. Chaikin & T.C. Lubensky, Principles of Condensed Matter Physics (Cambridge Univ.
Press, 2000); (2) R.G. Larson, The Structure and Rheology of Complex Fluids (Oxford Univ. Press, 1999); (3) P-G de Gennes and J. Prost, The Physics of Liquid Crystals (Clarendon, Oxford, 1993),
2nd Ed. (4) R.A.L. Jones, Soft Condensed Matter (Oxford Univ. Press, 2003); (5) I. W. Hamley, Introduction to Soft Matter (Wiley, 2000); (6) M. Kleman and O. Lavrentovich, Soft Matter Physics: an introduction (Springer, 2003); (7) M. Daound and C.E. Williams (eds.), Soft Matter Physics (Springer, 1999); (8) P. Oswald and P. Pieranski, Nematic and Cholesteric Liquid Crystals (Taylor & Francis,
2005); (9) P. Oswald and P. Pieranski, Smectic and Columnar Liquid Crystals (Taylor & Francis,
2006).
![Page 24: Chapter 1: Soft Condensed Matter](https://reader034.vdocument.in/reader034/viewer/2022052204/55cf9c00550346d033a83127/html5/thumbnails/24.jpg)
Additional Texts 1. RAL Jones Soft Condensed Matter OUP 2002 2. D Tabor Gases, Liquids and Solids, 3rd ed CUP 1991 3. M Daoud and CE Williams, Soft Matter Physics, Springer 1999 4. IW Hamley, Introduction to Soft Matter, Wiley 2000 5. P Nelson, Biological Physics, Freeman 2003 6. KW Dill and S Bromberg, Molecular Driving Forces, Garland Science 2003 7. SA Safran, Statistical Thermodynamics of Surfaces, Interfaces and Membranes, Addison Wesley 1994 8. M Daune, Molecular Biophysics, OUP 1999 9. JN Israelachvili Intermolecular and Surface Forces, Academic 1985 10. M Rubenstein and R Colby Polymer Physics,OUP 2003 11. PG de Gennes, F Brochard-Wyart and D Quéré, Capillarity and Wetting Phenomena Springer 2002 12. ME Cates and MR Evans, Soft and Fragile Matter, IoP 2000 13. IM Ward Mechanical Properties of Solid Polymers, Wiley 1983 14. IM Ward and J Sweeney, An Introduction to the Mechanical Properties of Solid Polymers, Wiley 2004 15. S Vogel Life in Moving Fluids Princeton 1994 16. RAL Jones Soft Machines OUP 2004 17. J Goodwin Colloids and Interfaces with Surfactants and Polymers Wiley 2004 18. M Doi Introduction to Polymer Physics OUP 1992 19. R Balescu Statistical Dynamics, Imperial College Press 1997 20. D Boal Mechanics of the Cell, CUP 2002 21. DC Bassett Principles of Polymer Morphology CUP 1981 22. AM Donald, AH Windle and S Hanna, Liquid Crystalline Polymers, CUP 2006 23. JR Waldram, The theory of thermodynamics 24. WCK Poon and D Andelman, eds, Soft Condensed Matter Physics in Molecular and Cell Biology, Taylor and
Francis 2006