Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Temperature dependence of the damping constant and the order parameter close to the lambda phase transitions in ammonium halides
Date
2006-10-01
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
189
views
0
downloads
Cite This
This study gives our calculation for the damping constant, using the expressions derived for an Ising pseudospin-phonon coupled system in the ammonium halides (NH4Cl and NH4Br). For this calculation of the damping constant, we use the temperature dependence of the order parameter calculated from the molecular field theory. We predict here the damping constants for the v(5) (174 cm(-1)) and v(5) (177 cm(-1)) Raman modes of NH4Cl and NH4Br, respectively, below T-lambda and compare them with our observed bandwidths measured as a function of temperature for those phonon modes at zero pressure.
Subject Keywords
Instrumentation
,
Analytical Chemistry
,
Spectroscopy
,
Atomic and Molecular Physics, and Optics
URI
https://hdl.handle.net/11511/36136
Journal
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
DOI
https://doi.org/10.1016/j.saa.2005.10.054
Collections
Department of Physics, Article
Suggestions
OpenMETU
Core
Temperature and pressure dependence of the mode Gruneisen parameters close to the melting point in hexagonal ice
Karacali, H.; Yurtseven, Hasan Hamit (Elsevier BV, 2007-02-01)
We reexamine the Pippard relations in this study by relating the specific heat C-P to the Raman frequency shifts 1/v(partial derivative v/partial derivative T)(P) and the thermal expansivity alpha(p) to the 1/v(partial derivative v/partial derivative P)(T), when the mode Gruneisen parameter depends on the temperature and pressure close to the melting point in hexagonal ice. From linear relations between them, the values of the slope dP/dT are deduced in this crystal.
Analysis of the Raman intensities near the phase transitions in ammonium halides
Yurtseven, Hasan Hamit (Elsevier BV, 2008-12-01)
This study concentrates on the temperature dependence of the Raman intensities for the lattice modes in ammonium halides (NH4Cl and NH4Br) close to phase transitions, We predict their intensities using the results of a shell model for the Raman polarizability within the framework of an Ising pseudospin-phonon coupled model.
Raman frequency shifts of an internal mode near the tricritical and second order phase transitions in NH4Cl
Yurtseven, Hasan Hamit (Elsevier BV, 2005-12-01)
This study gives our analysis for the frequency shifts of the nu(2)(1708 cm(-1)) Raman mode in NH4Cl close to its tricritical (P = 1.6 kbar) and second order (P = 2.8 kbar) phase transitions. From our analysis, we extract the values of the critical exponent which describes the critical behavior of the Raman frequency shifts for this internal mode for the pressure conditions studied in NH4Cl. Our exponent value of alpha approximate to 0.2 for the tricritical phase transition is close to the values of 1/16 (T...
Spectroscopic modification of the Pippard relation applied for the translational mode in ammonia solid II near the melting point
Yurtseven, Hasan Hamit; Yıldız, İlker (Elsevier BV, 2005-09-01)
This study gives our calculation for the frequency shifts 1/V(partial derivative v/partial derivative T)(P) and the specific heat C-p near the melting point in the ammonia solid II. We establish a linear relationship between C-p and 1/v(partial derivative v/partial derivative T)(P) using the Raman frequencies of the translational mode which we calculated in this system. This leads to the validity of the spectroscopic modification of the first Pippard relation in the ammonia solid II near the melting point. ...
Bandwidths studied as a function of temperature in ammonium halides near T-lambda
Yurtseven, Hasan Hamit (Elsevier BV, 2005-12-01)
This study gives our analysis of the Raman bandwidths using the soft mode-hard mode coupling model applied to ammonium halides. The temperature dependence of our observed bandwidths for the nu(5)(174 cm(-1)) Raman mode of NH4Cl and nu(5)(177 cm(-1)) Raman mode of NH4Br, is analyzed close to phase transitions. From our analysis, we obtain beta = 0.13 as the values of the critical exponent for the order parameter in the first order phase region for the ammonium halides.
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
H. H. Yurtseven, “Temperature dependence of the damping constant and the order parameter close to the lambda phase transitions in ammonium halides,”
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
, pp. 421–427, 2006, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/36136.