Resonant frequency shifts related to the elastic constants near the alpha-beta transition in quartz

Date

2019-03-05

Author

Yurtseven, Hasan Hamit

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The resonant frequency shifts of vibrational modes are related to the elastic constants at various temperatures for the alpha-beta transition in quartz (T-c = 573.0 degrees C for alpha-quartz and 574.3 degrees C for beta-quartz). This correlation is constructed on the basis of the spectroscopic modifications of the Pippard relations near the alpha-beta transition in quartz by using the observed data from the literature.

Subject Keywords

Inorganic Chemistry, Organic Chemistry, Analytical Chemistry, Spectroscopy

URI

https://hdl.handle.net/11511/43558

Journal

JOURNAL OF MOLECULAR STRUCTURE

DOI

https://doi.org/10.1016/j.molstruc.2018.11.044

Collections

Department of Physics, Article

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Critical behaviour of the specific heat calculated using the Raman frequencies of the lattice and internal modes near the lambda-phase transition in NH4Br Sen, S.; Yurtseven, Hasan Hamit (Elsevier BV, 2007-05-27) We calculate here the specific heat of NH4Br using our Raman frequency shifts for the lattice mode Of nu(7) TA (56 cm(-1)) and the internal mode Of nu(2) (1684 cm(-1)) near its lambda-phase transition (T-lambda = 234 K, P = 0). By analyzing our Raman frequency shifts, values of alpha = 0. 19 (T < T-lambda, and T > T-lambda) for the lattice mode, and alpha = 0.45 (T < T-lambda) and alpha = 0.57 (T > T-lambda) for the internal mode, are used as the values of the critical exponent for the specific heat to pred...
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Vibrational frequencies studied as a function of pressure in phase II of solid benzene Yurtseven, Hasan Hamit; Kilit, E. (Elsevier BV, 2011-05-03) The pressure dependence of the vibrational frequencies of six Raman modes is analyzed in phase II of solid benzene. The frequency shifts 1/nu(partial derivative nu/partial derivative P)(T) of those Raman modes are deduced from this analysis and they are related to the isothermal compressibility kappa(T)= -(1/V)(partial derivative V/partial derivative P)(T) through a constant isothermal mode Gruneisen parameter gamma(T) in phase II of solid benzene. The kappa(T) values predicted here are compared with the ka...
Pippard relations modified by the Raman frequency shifts for the phases I and II in NH4I Yurtseven, Hasan Hamit (Elsevier BV, 2009-04-30) Pippard relations in terms of the frequency shifts of the v(7) (40 cm(-1)) lattice mode, are established here for the phases I and II in NH4I. The temperature-induced frequency shift, (1/v)(partial derivative v/partial derivative T)(P) is calculated through the isobaric mode Gruneisen parameter gamma(P) using the lattice parameter data at zero pressure for the phases I and II in NH4I. From the frequency shifts, the specific heat C-P is calculated for the phases studied at zero pressure. Also, the pressure-i...
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Citation Formats

H. H. Yurtseven, “Resonant frequency shifts related to the elastic constants near the alpha-beta transition in quartz,” JOURNAL OF MOLECULAR STRUCTURE, pp. 421–424, 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/43558.