Crystal field splitting in the far infrared spectrum of rhombic sulfur

1969 ◽  
Vol 47 (14) ◽  
pp. 2713-2715 ◽  
Author(s):  
A. Anderson ◽  
L. Y. Wong
Keyword(s):  
Theoretical Analysis ◽  
Infrared Spectrum ◽  
Crystal Field ◽  
Far Infrared ◽  
Unit Cell ◽  
Crystal Field Splitting ◽  
Lattice Vibrations ◽  
Normal Coordinate ◽  
Thin Polycrystalline ◽  
Group Theoretical Analysis

The infrared (i.r.) spectra of thin polycrystalline samples of orthorhombic sulfur at 95 °K in the range 50–500 cm−1 have been recorded. The three i.r. active fundamentals ν4, ν5, and ν6 are observed to be split into 2,3, and 3 components, respectively, as predicted from a group theoretical analysis of the unit cell symmetry, thus confirming the assignment of ν4 and ν6. Several weaker absorptions are assigned by comparison with recent Raman results and a normal coordinate analysis. No peaks assignable to lattice vibrations are observed.

Group Theoretical Analysis of Lattice Vibrations in GaSe Polytypes

1974 ◽  
Vol 52 (24) ◽  
pp. 2454-2458 ◽  
Author(s):  
S. Jandl ◽  
J. L. Brebner
Keyword(s):  
Theoretical Analysis ◽  
Raman Scattering ◽  
Brillouin Zone ◽  
Wave Vector ◽  
Lattice Vibrations ◽  
Group Theoretical Analysis

We present here a group theoretical analysis of the lattice vibrations of the ε and γ polytypes of GaSe for different directions of the wave vector in the Brillouin zone. The effect of the interlayer interactions and the assignment of the modes observed in Raman scattering is discussed.

Gitterschwingungsspektren. XV. FIR-Spektren und Schwingungsanalyse von FeS2-Markasit / Lattice Vibration Spectra. XV. FIR-Spectra and Vibration Analysis of FeS2 Marcasite

1975 ◽  
Vol 30 (11) ◽  
pp. 1458-1461
Author(s):  
H. D. Lutz ◽  
P. Willich
Keyword(s):  
Theoretical Analysis ◽  
Vibration Analysis ◽  
Lattice Vibration ◽  
Normal Incidence ◽  
Vibrational Modes ◽  
Lattice Vibrations ◽  
Vibration Spectra ◽  
Symmetry Coordinates ◽  
Fir Spectra ◽  
Group Theoretical Analysis

The infrared-active lattice vibrations of the orthorombic marcasite (FeS2) have been studied by measuring the reflectivity of different crystal faces at near-normal incidence. A group-theoretical analysis predicts seven infrared-active modes (k = 0). Cartesian symmetry coordinates as well as vibrational modes of the lattice vibrations are constructed

Infrared Spectra of Matrix Isolated Alkali Tetrafluoroaluminates, AlkAlF4 (g)

1979 ◽  
Vol 34 (9) ◽  
pp. 1118-1129 ◽  
Author(s):  
Reidar Huglen ◽  
Sven J. Cyvin ◽  
Harald A. Øye
Keyword(s):  
Infrared Spectroscopy ◽  
Theoretical Analysis ◽  
Alkali Metal ◽  
Potential Energy ◽  
Structural Model ◽  
Vapour Phase ◽  
Potential Energy Distribution ◽  
Normal Coordinate ◽  
Bridge Bond ◽  
Group Theoretical Analysis

Abstract The 1 : 1 adduct compounds which are the prevailing vapour species over equimolar mixtures of AlkF and AlF3 (Alk = Li, Na, K, Rb and Cs) in the temperature range 450-750°C have been isolated in argon and nitrogen matrices and examined bv infrared spectroscopy. Seven frequencies which are assigned to matrix isolated alkali tetrafluoroaluminate molecules have been found for all systems investigated. Group theoretical analysis and subsequent normal coordinate computations of the reassigned frequencies confirm a structural model for the AlkAlF4 molecules having the symmetry C2v-However, the results from this analysis cannot be taken as a definite confirmation of a true bidentate structure for these molecules in the vapour phase. The alkali metal-fluorine bond is found to be rather weak, and the Al-F terminal bond is found to be stronger than the Al-F bridge bond. Qualitative relations between matrix as well as vibrational shifts and potential energy distribution are discussed.

Sign in / Sign up

Export Citation Format

Share Document