Local lattice relaxation around Tl substitutional impurities in a NaI(Tl) scintillator crystal

2020 ◽  
Vol 177 ◽  
pp. 108992
Author(s):  
A. Filipponi ◽  
G. Profeta ◽  
N. Di Marco ◽  
V. Zema ◽  
K. Schäffner ◽  
...  
Keyword(s):  
Lattice Relaxation ◽  
Local Lattice ◽  
Substitutional Impurities ◽  
Scintillator Crystal

SUPERPOSITION MODEL ANALYSIS FOR THE ZERO-FIELD SPLITTING OFMn2+IN SOME CRYSTALS

2006 ◽  
Vol 20 (30) ◽  
pp. 1917-1922 ◽  
Author(s):  
VIMAL KUMAR JAIN
Keyword(s):  
Lattice Relaxation ◽  
Zero Field ◽  
Superposition Model ◽  
Zero Field Splitting ◽  
Intrinsic Parameter ◽  
Order Zero ◽  
Field Splitting ◽  
Zero Field Splitting Parameter ◽  
Local Lattice ◽  
Splitting Parameter

The Newman superposition model has been applied to second-order zero-field splitting parameter [Formula: see text] taken from the literature for Mn2+in Hg(ClO4)2· 6 H2O , M ″ SiF6·6 H2O (M ″= Fe, Co, Zn ) and M ″ NbOF5·6 H2O (M ″= Co, Zn ). In the calculations, the local lattice relaxation has been taken into account. It is shown that nearly the same value of intrinsic parameter b2=-0.057(8) cm-1is obtained.

Theoretical Investigations of the EPR Parameters of Ti3+ in Beryl Crystal

2006 ◽  
Vol 61 (5-6) ◽  
pp. 286-288 ◽  
Author(s):  
Wen-Chen Zheng ◽  
Qing Zhou ◽  
Xiao-Xuan Wu ◽  
Yang Mei
Keyword(s):  
Hyperfine Structure ◽  
Reasonable Agreement ◽  
Lattice Relaxation ◽  
Superposition Model ◽  
Theoretical Investigations ◽  
Local Lattice ◽  
Epr Parameters ◽  
Structure Constants ◽  
Experimental Values ◽  
Crystal Field Parameters

The EPR parameters (g factors gII, g⊥ and hyperfine structure constants AII, A⊥) of Ti3+ ion at the sixfold coordinated Al3+ site with trigonal symmetry in beryl crystal are calculated by the thirdorder perturbation formulas of 3d1 ions in a trigonal octahedron. In the calculations, the crystal-field parameters are obtained by the superposition model, and the impurity-induced local lattice relaxation (which is similar to that found for Fe3+ in beryl) is considered. The calculated EPR parameters (and also the optical spectra) are in reasonable agreement with the experimental values

LOCAL LATTICE RELAXATION AROUND 5 sp IMPURITIES IN IRON, NICKEL AND SILICON

1986 ◽  
Vol 47 (C8) ◽  
pp. C8-1049-C8-1052
Author(s):  
T. J. VAN NETTE ◽  
K. STAPEL ◽  
L. NIESEN
Keyword(s):  
Lattice Relaxation ◽  
Local Lattice ◽  
Iron Nickel

scholarly journals Dynamical Mechanism of Polarons and Bipolarons in Poly(p-Phenylene Vinylene)

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Fábio Luís de Oliveira Paula ◽  
Leonardo Luiz e Castro ◽  
Luiz Antonio Ribeiro Junior ◽  
Rafael Timóteo de Sousa Júnior ◽  
Geraldo Magela e Silva ◽  
...  
Keyword(s):  
Transport Mechanism ◽  
Tight Binding ◽  
Lattice Relaxation ◽  
Phenylene Vinylene ◽  
Dynamical Mechanism ◽  
Light Emitting ◽  
Chemical Structures ◽  
Relaxation Effects ◽  
Local Lattice ◽  
The Relationship

AbstractStudies on Poly(p-Phenylene Vinylene) (PPV) and derivatives have experienced enormous growth since they were successfully used to fabricate the first efficient prototypes of Polymer Light-Emitting Diodes in the 90s. Despite this rapid progress, understanding the relationship between charge transport and the morphology in these materials remains a challenge. Here, we shed light on the understanding of the transport mechanism of polarons and bipolarons in PPVs by developing a two-dimensional tight-binding approach that includes lattice relaxation effects. Remarkably, the results show that the PPV lattice loses the energy related to its conjugation during time by transferring this amount of energy to electrons. Such a process for energy transfer permits the quasiparticles to overcome the potential barrier imposed by the local lattice deformations, that are formed in the presence of an additional charge and, consequently, their electric field assisted transport takes place. Within the framework of this transport mechanism, a better insight into the origin of the carrier mobility in PPV and derivatives can be achieved and would be a useful guide for improving their chemical structures and morphologies.

Theoretical Interpretation of the EPR Parameters for Dy3+ Ion in LuPO4 Crystal

2004 ◽  
Vol 59 (11) ◽  
pp. 765-768 ◽  
Author(s):  
Hui-Ning Dong ◽  
Hui-Ping Du ◽  
Shao-Yi Wu ◽  
Peng Li
Keyword(s):  
Field Theory ◽  
Hyperfine Structure ◽  
Crystal Field ◽  
Lattice Relaxation ◽  
Theoretical Interpretation ◽  
Superposition Model ◽  
Crystal Field Theory ◽  
Local Lattice ◽  
Epr Parameters ◽  
Structure Constants

Based on the superposition model, in this paper the EPR parameters gII and g⊥ of Dy3+, and the hyperfine structure constants AII and A⊥ of 161Dy3+ and 163Dy3+ in LuPO4 crystal are calculated by perturbation formulas from the crystal-field theory. In the calculations, the contributions of various admixtures and interactions such as J-mixing, mixtures among states with the same J-value, twoorder perturbation, covalency as well as local lattice relaxation are considered. The calculated results agree reasonably with the observed values

Sign in / Sign up

Export Citation Format

Share Document