Analysis of the Specific Heat for the Transitions of the Phases I-II-III-IV in (N(CH3)(4))(2)CUCl4 Crystal

Date

2008-01-01

Author

Yurtseven, Hasan Hamit

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

112
views

0
downloads

The temperature dependence of the specific heat C-p is analyzed here using the experimental data according to a power-law formula with the critical exponent a for the transitions of commensurate (I), incommensurate (II) and the ferroelastic (III and IV) phases in (N(CH3)(4))(2)CUCl4 crystal. From our analysis, we extract the value of a approximate to 0 above and below T-c for the successive phase transitions of which is expected from the mean field theory (alpha =0 discontinuity), XY model (alpha =0 log) and the two dimensional Ising model (alpha =0 log). This indicates that the transitions between commensurate and incommensurate phases and also between incommensurate and ferroelastic (III) phases in TMATC-Cu are of a second order type.

Subject Keywords

Dielectric a2bx4 family, <n(ch3)4>2cucl4, (n(ch3)4)2cucl4, Ferroelectricity, Incommensurate, Modulated phases, Elastic properties

URI

https://hdl.handle.net/11511/53908

Journal

HIGH TEMPERATURE MATERIALS AND PROCESSES

Collections

Department of Physics, Article

Suggestions

OpenMETU
Core

Investigation of the incommensurate (INC) phase between α and β phases in quartz and related materials Ateş, Simge; Yurtseven, Hasan Hamit; Department of Physics (2021-2-10) Incommensurate (INC) phase as an intermediate sinusoidal phase which exists in anarrow temperature range (∼1.3◦C) between the low-temperatureαand the high-temperatureβphases in quartz, is investigated extensively. The phase transitions oftheα-INC and INC-βoccurring as first order and second order type, respectively,are studied using the experimental data from the literature. Order-disorder transi-tion between theαandβquartz through the incommensurate phase is described bytemperature and pressure dependen...
Analysis of the Critical Magnetic Field and the Dielectric Susceptibility for the Smectic A-Smectic C* Transition in DOBAMBC Yurtseven, Hasan Hamit (2015-01-01) The temperature dependences of the critical magnetic field H-c and the dielectric susceptibility x(at constant magnetic fields) are analyzed close to the smectic Asmectic C* transition in DOBAMBC using the experimental data according to a power-law formula. These analyses are performed below T-c in the smectic C* phase. Values of the critical exponent delta for the critical magnetic field are determined in a given temperature interval (Tc-T) with increasing and decreasing H-c. Also, values of the critical e...
Calculation of the Raman Linewidths of Lattice Modes Close to the alpha-beta Transition in Quartz Lider, Mustafa Cem; Yurtseven, Hasan Hamit (Walter de Gruyter GmbH, 2012-12-01) The Raman frequencies of the lattice modes (147 cm(-1) and 207 cm(-1)) are analyzed for the alpha-beta transition in quartz according to a power-law formula with the critical exponent by using the experimental data. The temperature dependence of the Raman frequency is associated with the order parameter (polarization P) for this transition in the quartz crystal.
Calculation of the specific heat using the Raman frequency shifts for the solid I-II transition in benzene Yurtseven, Hasan Hamit (Elsevier BV, 2015-06-15) The specific heat C-p is calculated as a function of temperature using the observed Raman frequency shifts of the six lattice modes at constant pressures of 0 and 0.1 GPa for the solid I-II transition in benzene. This calculation is performed using the volume data through the mode Grfineisen parameter of each lattice mode which we determined as functions of temperature and pressure. The specific heat C-p is also calculated as a function of pressure at room temperature using the Raman frequency shifts of tho...
Analysis of the Specific Heat in the Supercooled Solid Phase of Liquid Crystals Kilit, Emel; Yurtseven, Hasan Hamit (Informa UK Limited, 2011-01-01) The specific heat Cp is analyzed using the experimental data at various temperatures in the solid phase of cholesteryl myristate according to a power-law formula for the rapidly and slowly cooled solid in the stability limit. We also analyze the temperature dependence of the Cp using the experimental data for the supercooled solid phase of p-azoxyanisole in the stability limit and the stability temperatures are determined for both cholesteryl myristate and p-azoxyanisole.

Citation Formats

H. H. Yurtseven, “Analysis of the Specific Heat for the Transitions of the Phases I-II-III-IV in (N(CH3)(4))(2)CUCl4 Crystal,” HIGH TEMPERATURE MATERIALS AND PROCESSES, pp. 135–140, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/53908.