Plasticity in body-centred cubic (BCC) metals at low temperatures is atypical, marked in particular by an anisotropic elastic limit in clear violation of the famous Schmid law applicable to most other metals. This effect is known to originate from the behaviour of the screw dislocations; however, the underlying physics has so far remained insufficiently understood to predict plastic anisotropy ...

A random matrix approach to glassy physics is introduced. It leads to a class of models that exhibit both glassy low-temperature phases and doubleand single-well configurations in their potential energy. The distribution of parameters characterizing the local potential energy configurations can be computed, and differ from those assumed in the standard tunneling model and its variants. Still, l...

We compute a new potential energy surface (PES) for the study of the inelastic collisions between N2H(+) and H2 molecules. A preliminary study of the reactivity of N2H(+) with H2 shows that neglecting reactive channels in collisional excitation studies is certainly valid at low temperatures. The four dimensional (4D) N2H(+)-H2 PES is obtained from electronic structure calculations using the cou...

The simple structures formed by charged particles confined in a harmonic potential have been investigated and the configurations of minimum potential energy were identified. For fewer than 12 particles these form polyhedrons centered on the origin. For structures with 13-22 particles one sits in the middle, for 23-26 particles two are in the interior, etc., until a third shell starts forming at...

The hydrogen-bond network formed from a crystalline solution of ferroelectric RbH2PO4 and antiferroelectric NH4H2PO4 demonstrates glassy behavior, with proton tunneling the dominant mechanism for relaxation at low temperature. We characterize the dielectric response over seven decades of frequency and quantitatively fit the long-time relaxation by directly measuring the local potential energy l...

Through the study of the C3(X1Σg (+)) (1)Σg (+)) + He((1)S) astrophysical relevant system using standard (CCSD(T)) and explicitly correlated (CCSD(T)-F12) coupled cluster approaches, we show that the CCSD(T)-F12/aug-cc-pVTZ level represents a good compromise between accuracy and low computational cost for the generation of multi-dimensional potential energy surfaces (PESs) over both intra- and ...

it is very important to find the best model to quantify seed germination rate on the response of temperature which it can be used in determination of cardinal temperatures. this study was conducted to evaluation nonlinear regressions models for description wheat (cv. morvarid) germination rate response to temperatures and water potentials. therefore, seeds germination rate were evaluated in tem...

in this study, a temperature-dependent of the dispersion coefficients is calculated from equation state.the lennard-jones lj (12-6-3) effective pair potential function and simple thermodynamic argumentwith the input pvt data of liquid metals are used to calculate the dispersion coefficients. the dispersioncoefficients ( , , ) 3 6 12 c c c are found to be a linear function of 1/t1+α , where t is...