Premium
On Coherent Neutron Diffraction in Nematic Liquid Crystals
Author(s) -
Cvikl B.
Publication year - 1978
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.2220880103
Subject(s) - liquid crystal , neutron diffraction , diffraction , structure factor , anisotropy , neutron , biaxial nematic , neutron scattering , optics , phase (matter) , condensed matter physics , small angle neutron scattering , intermolecular force , materials science , physics , scattering , molecular physics , molecule , nuclear physics , quantum mechanics
The differential cross‐section of the coherent neutron diffraction in the nematic phase is derived. It is shown that spontaneous distortions, which enter the theory through the intermolecular part of the structure factor and may be associated with two different diffusive optic soft modes of this phase, influence the neutron diffraction patterns through the correlations in space of the preferred molecular axes. The structure factor is anisotropic and exhibits for 1 Å −1 < Q < 4 Å −1 two distinct peaks depending on the relative orientation of the neutron scattering vector and the uniaxial nematic direction in quantitative agreement with the observations. For 0.4 Å −1 < Q < 1 Å −1 an intense peak is obtained in the calculations.