04/19/23

l sl

ls

ss

s

s

l

l

lls

s ll

P1121/m

ss

ll

b

Synchrotron powder diffraction on La1/2Ca1/2MnO3: P. Radaelli et al.

Phys. Rev. B 55, 3015 (1997)

Mn3+

Mn4+

P21nm

ll

lll

ll

l

lll

ls

s

ss

ss

s

s

sss

s

Neutron Diffraction on a Pr0.60Ca0.40MnO3 twinned single crystal :

A. Daoud-Aladine, et al.

Phys. Rev. Lett 89, 97205 (2002)

sss s

sss s

Transverse modulation amplitudes

(I) Why a neutron diffraction study on single crystal ?

04/19/23

Twinned CrystalDiffraction plane at T<TCO

(I) Why a neutron diffraction study on single crystal ?

Possibly up to 6 domain contributions

1,2

3,4

5,6

Basic structure peaks of different orthorhombic domains overlap (circles)

Powder diffraction at T<TCO

Superlattice peaks (triangles)

Max=50000 !!

Pr0.60Ca0.40MnO3 BM16-ESRF

Synchrotron powder diffraction on Pr0.60Ca0.30MnO3: D. E. Cox et al.

Phys. Rev. B 57, 3305 (1998)

Q(Å-1)

only 10 up to 14 groups of superstructure reflections

Superstructures q=(0 ½ 0)

b*

a*

( 1 -1 0)1

(-1 -1 0)2

( 1 1 0)3

(-1 1 0)4

( 0 0 2)5

( 0 0 2)6