Premium
Raman spectral studies of single crystal CH 3 ND 3 NO 3
Author(s) -
Mylrajan M.,
Srinivasan T. K. K.
Publication year - 1987
Publication title -
journal of raman spectroscopy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.748
H-Index - 110
eISSN - 1097-4555
pISSN - 0377-0486
DOI - 10.1002/jrs.1250180512
Subject(s) - raman spectroscopy , chemistry , phase transition , isotropy , deuterium , single crystal , atmospheric temperature range , crystal (programming language) , spectral line , lattice (music) , analytical chemistry (journal) , nuclear magnetic resonance , crystallography , condensed matter physics , thermodynamics , optics , atomic physics , physics , programming language , chromatography , astronomy , computer science , acoustics
Raman spectra of single crystal N ‐deuterated methylammonium nitrate (CH 3 ND 3 NO 3 ) were studied in the temperature range 77–400 K. A systematic temperature dependence study of the internal and external modes was carried out. The results show the preseuce of three structural phases. Raman spectra of phase II in the internal and lattice region were interpreted on the basis of a D 2h 16space group and relative polarization data. A thermal hysteresis characteristic of a first‐order transition was observed in theThe spectral features of phase I indicate this to be a plastic phase, in which cations and anions exhibit isotropic reorientational motion. The spectral changes that occur in thetransition suggest a freezing out of the thermal motion and reveal that only minor changes are involved in this transition.