NQR Pressure Studies of Molecular Dynamics and Phase Transitions
نویسنده
چکیده
High pressure technique applied in studies of NQR frequency and quadrupole relaxation has been used for deriving information on the dynamical properties of crystals and the nature of their phase transitions. The ^Cl NQR pressure studies have been carried out and a detailed analysis is given for the following topics: 1) Symmetric and asymmetric hydrogen bonded systems under high pressure. 2) NQR pressure studies of the system with soft zonecenter optic phonons.
منابع مشابه
GCMC Glauber dynamics study for structural transitions in YBCOx (0<x<1), HTc system
We have chosen an Ising ASYNNNI (ASYmmetric Next Nearest Neighbor Interaction) model under a grand canonical regime to investigate structural phase transition from a high symmetric tetragonal (Tet) to a low symmetric orthorhombic in YBa2Cu3O6+x , 0<x<1, HTc system. Ordering process for absorbed oxygens from an external gas bath into the basal plane of the layered system is studied by Monte C...
متن کاملNUMERICAL SIMULATIONS OF THE PHASE TRANSITIONS IN CLUSTERS
We have studied the phase transitions in atomic clusters by molecular dynamics simulation, assuming Lennard-Jones interatomic pair potential. Calculations are performed by DAP parallel computer. The results are analyzed by simulating their orientational distribution plots (dot-plot), and neutron diffraction patterns. It is shown that all the main features of the bulk phase transitions are e...
متن کاملDynamic Properties and Phase Transitions in A2ZnBr4 (A= (CH3)4N and (CH3)4P) as Studied by Br NQR and Multinuclear NMR*
In order to understand the mechanism of ferroelastic phase transitions in A2ZnBr4 (A = (CH3)4N and (CH3)4P), the temperature dependences of Br NQR frequencies and the spin-lattice relaxation times were measured. The temperature dependences of the 'H and P spin-lattice relaxation times were measured as well for a possible correlation between the cation dynamics and the phase transition. Although...
متن کاملIodine NQR and Phase Transitions in [N(CH3)4]2ZnI4*
Using a superregenerative NQR spectrometer, the temperature dependence of I NQR spectra in [N(CH3)4]2ZnI4 was measured between 167 and 335 K. The measurements confirm two known structural phase transitions at 219 and 257.5 K. The correspondence between the distinct regions of iodine NQR spectra and the crystal structure is discussed. The relation of [N(CH3)4]2ZnI4 to the incommensurate family w...
متن کاملNMR • NQR and DTA • DSC Studies of Phase Transitions in Pyridinium Tetrachloropalladate(II) and Pyridinium Tetrachloroplatinate(II)*
für Naturforschung in cooperation with the Max Planck Society for the Advancement of Science under a Creative Commons Attribution 4.0 International License. Dieses Werk wurde im Jahr 2013 vom Verlag Zeitschrift für Naturforschung in Zusammenarbeit mit der Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V. digitalisiert und unter folgender Lizenz veröffentlicht: Creative Commons Namen...
متن کامل