Lattice dynamics and migration enthalpies inCoPt3and FePd

Lattice enthalpies, polarizabilities and shear moduli of lanthanide orthophosphates LnPO4.

Lattice energies ΔLHθ of lanthanide orthophosphates, LnPO4 (Ln=Ce-Lu, excluding Pm) have been determined from the Born-Haber cycle and compared with those calculated by other methods. The Born-Haber cycle results in close values of ΔLHθ to those obtained after an empirical equation proposed by Glasser and Jenkins. It has been found that: (i) the partial derivative of the lattice enthalpies to t...

Partial molar enthalpies and reaction enthalpies from equilibrium molecular dynamics simulation.

We present a new molecular simulation technique for determining partial molar enthalpies in mixtures of gases and liquids from single simulations, without relying on particle insertions, deletions, or identity changes. The method can also be applied to systems with chemical reactions. We demonstrate our method for binary mixtures of Weeks-Chandler-Anderson particles by comparing with convention...

Diffusive and percolative lattice migration: Excitonsa)

A microscopic transport theory is developed for stochastic and correlated hopping on ordered and random lattices that contain a small fraction of supertraps and a small number of "hoppers" (Le., excitons). It includes short-time ("transient") behavior, which is of interest for both time-resolved and steady-state experiments. The relations with diffusion, percolation, random walk, and rate equat...

Lattice Dynamics of Tetracyanoethylene

Dynamics of lattice kinks

We consider a class of Hamiltonian nonlinear wave equations governing a field defined on a spatially discrete one dimensional lattice, with discreteness parameter, d = h, where h > 0 is the lattice spacing. The specific cases we consider in detail are the discrete sine-Gordon (SG) and discrete φ models. For finite d and in the continuum limit (d → ∞) these equations have static kink-like (heter...