Vibrational analysis of the low resolution absorption spectra of BrClCS and Br2CS

1988 ◽  
Vol 66 (3) ◽  
pp. 359-366 ◽  
Author(s):  
B. Simard ◽  
R. P. Steer ◽  
R. H. Judge ◽  
D. C. Moule
Keyword(s):  
Absorption Spectra ◽  
Room Temperature ◽  
Vibrational Analysis ◽  
Vibrational Frequencies ◽  
Low Resolution ◽  
Barrier Heights ◽  
Vibrational Levels ◽  
Out Of Plane ◽  
The Given

The [Formula: see text] absorption spectra of BrClCS and Br2CS have been photographed under low resolution at room temperature. The electronic origins of BrClCS and Br2CS have been placed at 17116 and 16859 cm−1, respectively. Vibronic analyses show that the molecules are non-planar in their ā states. By fitting quadratic–Gaussian and quadratic–quartic double-minimum potentials to the observed vibrational levels of the out-of-plane manifolds, the equilibrium out-of-plane angles and the barrier heights to molecular inversion have been estimated to be 25 ± 1 deg and 541 ± 10 cm−1 for BrClCS, and 17.5 ± 1 deg and 524 ± 10 cm−1 for Br2CS. In the case of BrClCS, all six ā state vibrational frequencies have been obtained. In the case of Br2CS, only modes 1 (C—S stretch), 2 (symmetric C—Br stretch), 3 (in-plane Br—C—Br scissor), and 4 (out-of-plane bend) are active in the spectrum. Comparisons with other tetraatomic thiocarbonyls support the given assignments.

Pressure dependent ultrasonic properties of hcp hafnium metal

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ramanshu P. Singh ◽  
Shakti Yadav ◽  
Giridhar Mishra ◽  
Devraj Singh
Keyword(s):  
Elastic Constants ◽  
Pressure Range ◽  
Room Temperature ◽  
Ultrasonic Attenuation ◽  
Coupling Constants ◽  
Ultrasonic Properties ◽  
Acoustic Coupling ◽  
Third Order Elastic Constants ◽  
The Stability ◽  
The Given

Abstract The elastic and ultrasonic properties have been evaluated at room temperature between the pressure 0.6 and 10.4 GPa for hexagonal closed packed (hcp) hafnium (Hf) metal. The Lennard-Jones potential model has been used to compute the second and third order elastic constants for Hf. The elastic constants have been utilized to calculate the mechanical constants such as Young’s modulus, bulk modulus, shear modulus, Poisson’s ratio, and Zener anisotropy factor for finding the stability and durability of hcp hafnium metal within the chosen pressure range. The second order elastic constants were also used to compute the ultrasonic velocities along unique axis at different angles for the given pressure range. Further thermophysical properties such as specific heat per unit volume and energy density have been estimated at different pressures. Additionally, ultrasonic Grüneisen parameters and acoustic coupling constants have been found out at room temperature. Finally, the ultrasonic attenuation due to phonon–phonon interaction and thermoelastic mechanisms has been investigated for the chosen hafnium metal. The obtained results have been discussed in correlation with available findings for similar types of hcp metals.

Preparation and Properties of La2O3-CaO-P2O5 Glasses Doped with Eu3+ Ions

2016 ◽  
Vol 675-676 ◽  
pp. 376-379 ◽  
Author(s):  
Narun Luewarasirikul ◽  
Piyachat Meejitpaisan ◽  
Jakrapong Kaewkhao
Keyword(s):  
Calcium Phosphate ◽  
Molar Volume ◽  
Absorption Spectra ◽  
Room Temperature ◽  
Emission Spectra ◽  
Phosphate Glasses ◽  
Excitation Wavelength ◽  
Melt Quenching ◽  
Volume Measurements ◽  
Doped Glasses

Lanthanum calcium phosphate glasses doped with Eu3+ ions in compositions 20La2O3:10CaO:(70-x)P2O5:xEu2O3 (where x = 0.05, 0.10, 0.50 and 1.50 mol%) were prepared by melt-quenching technique. The density and molar volume measurements were carried out at room temperature. The absorption spectra were investigated in the UV-Vis-NIR region from 200 to 2500 nm. The emission spectra of Eu3+-doped glasses centered at 590 nm (5D0→7F1), 612 nm (5D0→7F2), 652 nm (5D0→7F3) and 699 nm (5D0→7F4) have been observed with 393 nm excitation wavelength.

OPTICAL ABSORPTION AND ESR SPECTRAL STUDIES ON COPPER-DOPED LEAD-CADMIUM GLASSES

2005 ◽  
Vol 19 (03) ◽  
pp. 119-128 ◽  
Author(s):  
M. PRASAD ◽  
M. CHANDRASEKHAR ◽  
V. CHANDRA MOULI
Keyword(s):  
Optical Absorption ◽  
Absorption Spectra ◽  
Room Temperature ◽  
Spectral Studies ◽  
Optical Absorption Spectra ◽  
Prepared Glass ◽  
Spin Resonance ◽  
Spectral Profiles ◽  
Hamiltonian Parameters ◽  
Ligand Bond

The electron spin resonance and optical absorption spectra of PbO-CdO glasses containing 1 mole% CuO have been investigated at room temperature. The optical absorption spectra of all glass samples have exhibited a broad asymmetric absorption band, which corresponds to a d–d transition of Cu 2+ ions. The prepared glass samples have been analyzed as a function of the photon energy. The results are interpreted based on the optical absorption spectral profiles and also the edge values upon the application of Davis and Mott's theory. From the ESR spectral features, the spin Hamiltonian parameters have been evaluated. The bonding coefficients were obtained, in order to elucidate the information on the Cu 2+ ligand bond nature.

ChemInform Abstract: DIRECT OBSERVATION OF THE OPTICAL ABSORPTION SPECTRA OF REACTIVE FREE RADICALS AT ROOM TEMPERATURE

1974 ◽  
Vol 5 (44) ◽  
pp. no-no
Author(s):  
JIMMY E. JORDAN ◽  
DAVID W. PRATT ◽  
DAVID E. WOOD
Keyword(s):  
Free Radicals ◽  
Optical Absorption ◽  
Absorption Spectra ◽  
Direct Observation ◽  
Room Temperature ◽  
Optical Absorption Spectra

Overcoming the out-of-plane bending issue in an aromatic hydrocarbon: the anharmonic vibrational frequencies of c-(CH)C3H2+

2020 ◽  
Vol 22 (23) ◽  
pp. 12951-12958 ◽  
Author(s):  
Brent R. Westbrook ◽  
Weston A. Del Rio ◽  
Timothy J. Lee ◽  
Ryan C. Fortenberry
Keyword(s):  
Aromatic Hydrocarbon ◽  
Infrared Emission ◽  
Vibrational Frequencies ◽  
Out Of Plane ◽  
Plane Bending

Two vibrational frequencies for this molecule correlate with observed but unknown interstellar infrared emission features.

scholarly journals Phonon hydrodynamics and ultrahigh–room-temperature thermal conductivity in thin graphite

Science ◽  
2020 ◽  
Vol 367 (6475) ◽  
pp. 309-312 ◽  
Author(s):  
Yo Machida ◽  
Nayuta Matsumoto ◽  
Takayuki Isono ◽  
Kamran Behnia
Keyword(s):  
Thermal Conductivity ◽  
Thermal Diffusivity ◽  
Wide Temperature Range ◽  
Room Temperature ◽  
Phonon Dispersion ◽  
High Conductivity ◽  
Temperature Range ◽  
A Value ◽  
Out Of Plane ◽  
Intimate Link

Allotropes of carbon, such as diamond and graphene, are among the best conductors of heat. We monitored the evolution of thermal conductivity in thin graphite as a function of temperature and thickness and found an intimate link between high conductivity, thickness, and phonon hydrodynamics. The room-temperature in-plane thermal conductivity of 8.5-micrometer-thick graphite was 4300 watts per meter-kelvin—a value well above that for diamond and slightly larger than in isotopically purified graphene. Warming enhances thermal diffusivity across a wide temperature range, supporting partially hydrodynamic phonon flow. The enhancement of thermal conductivity that we observed with decreasing thickness points to a correlation between the out-of-plane momentum of phonons and the fraction of momentum-relaxing collisions. We argue that this is due to the extreme phonon dispersion anisotropy in graphite.

An irreversible phase transition in 1-n-butylindeno[2,1-c]pyran-3,9-dione

2012 ◽  
Vol 68 (10) ◽  
pp. o413-o416 ◽  
Author(s):  
Andrei S. Batsanov ◽  
Judith A. K. Howard ◽  
Na Wu ◽  
Zhen Yang ◽  
Todd B. Marder
Keyword(s):  
Phase Transition ◽  
Ambient Temperature ◽  
Single Crystal ◽  
Title Compound ◽  
Room Temperature ◽  
Side Chain ◽  
Compound C ◽  
Planar Conformation ◽  
Triclinic Phase ◽  
Out Of Plane

At ambient temperature, the title compound, C16H14O3, is triclinic, with then-butyl side chain disordered in an out-of-plane orientation. On cooling below 240 K, it converts into a different triclinic phase with an ordered planar conformation and denser packing, which is retained on warming to room temperature. The transition (occasionally) proceeds from single crystal to single crystal.

Primary Odors and Insect Attraction

1966 ◽  
Vol 98 (10) ◽  
pp. 1083-1093 ◽  
Author(s):  
R. H. Wright
Keyword(s):  
Statistical Analysis ◽  
Absorption Spectra ◽  
Infrared Absorption ◽  
Direct Evidence ◽  
Far Infrared ◽  
Vibrational Frequencies ◽  
Insect Attractants ◽  
Single Substance ◽  
Insect Attraction ◽  
Infrared Absorption Spectra

AbstractA statistical analysis of U.S.DA. studies of insect attractants provides the first direct evidence for the reality of "primary" odors (heretofore inferred indirectly from abstract principles). Molecules of a single substance may carry more than one primary osmic character and the presence of one does not preclude another, but some primaries may overlap others. Thus the molecular qualities responsible for osmic properties appear to be distributed along a continuum. Molecular vibrational frequencies are so distributed, and the far infrared absorption spectra of some attractant and non-attractant substances show correlations of the sort predicted by the theory.

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