The elastic behavior and stability of elemental crystals are studied in the neighborhood of a stable equilibrium state, also called a phase, at finite pressure p. It is shown that two kinds of elastic constants are needed to describe elasticity under pressure. One set, designated as c(ij),i,j = 1-6, determines stability or lack of it; another set, designated as c(ij)(p), describes the linear re...

We have measured the adiabatic elastic constants of two Cu-Al-Ni martensitic alloys using ultrasonic methods and we have compared the results to recent neutron-scattering experiments. It is shown that the elastic behavior of Cu-Al-Ni alloys follows the same trends exhibited by other Cu-based alloys; in particular, the TA2 long-wavelength acoustic modes are softer than all other modes. Disciplin...

Bayesian modeling and Hamiltonian Monte Carlo (HMC) are utilized to formulate a robust algorithm capable of simultaneously estimating anisotropic elastic properties and crystallographic orientation of a specimen from a list of measured resonance frequencies collected via Resonance Ultrasound Spectroscopy (RUS). Unlike typical optimization procedures which yield point estimates of the unknown pa...

We performed ab initio calculations of the elastic constants of five flexible metal-organic frameworks (MOFs): MIL-53(Al), MIL-53(Ga), MIL-47, and the square and lozenge structures of DMOF-1. Tensorial analysis of the elastic constants reveals a highly anisotropic elastic behavior, some deformation directions exhibiting very low Young's modulus and shear modulus. This anisotropy can reach a 400...

– We consider a simple model of a random heteropolymer chain that is known to undergo the freezing transition. We investigate the change in the elastic properties of the chain upon freezing. The elastic constants are evaluated and it is shown that they acquire a non-trivial contribution in the frozen phase. The goal of this letter is to investigate the elasticity of a random heteropolymer chain...

[1] Knowledge of the elastic properties and crystal chemistry of dense oxide structures plays an important role in interpreting the composition and mineralogy of planetary interiors. We report the effects of (Mg,Fe) substitution and nonstoichiometry due to Fe on the crystal structure, elastic constants (cij) and moduli (K0T, K0S, G0) of (Mg,Fe)O utilizing single-crystal X-ray diffraction and gi...

Elastic constants of two-dimensional (2D) colloidal crystals are determined by measuring strain fluctuations induced by Brownian motion of particles. Paramagnetic colloids confined to an air-water interface of a pendant drop are crystallized under the action of a magnetic field, which is applied perpendicular to the 2D layer. Using video microscopy and digital image processing we measure fluctu...

Ultrasonic attenuation due to phonon–phonon interaction and thermoelastic loss was evaluated in VIII group transition metal Pt in a wide temperature range (100 K to 1500 K) for longitudinal and shear waves along 〈100〉, 〈110〉 and 〈111〉 directions and for shear waves polarised along different directions. Electrostatic and Born–Mayer potentials were used to obtain second and third order elastic co...

The exoelectric e ect provides a linear coupling between electric polarization and orientational deformation in liquid crystals. It in uences many electrooptical phenomena and it is used in some bistable nematic devices. A statistical theory of dipole exoelectric polarization in biaxial nematic liquid crystals is used to calculate temperature dependence of order parameters, elastic constants, a...