相关论文: Thermal expansion and polyamorphism of N2 - C60 so…
Orientational glasses with CO molecules occupying 26% and 90% of the octahedral interstitial sites in the C60 lattice have been investigated by the dilatometric method in a temperature interval of 2.5 - 23 K. At temperatures 4 - 6 K the…
The dilatometric investigation in the temperature range of 2-28K shows that a first-order polyamorphous transition occurs in the orientational glasses based on C60 doped with H2, D2 and Xe. A polyamorphous transition was also detected in…
The low temperature (2-24 K) thermal expansion of pure (single crystal and polycrystalline) C60 and polycrystalline C60 intercalated with He, Ne, Ar, and Kr has been investigated using high-resolution capacitance dilatometer. The…
The heat capacity Cm of polycrystalline fullerite C60 doped with nitrogen has been measured in the temperature interval 2 - 13 K. The contributions to heat capacity from translational lattice vibrations (Debye contribution), orientational…
Thermal expansion of {\alpha}-rhombohedral boron ({\alpha}-B12) and two isostructural boron-rich pnictides (B12P2 and B12As2) has been studied between 298 and 1280 K by high-temperature synchrotron X-ray diffraction. For all studied phases…
The lattice parameters of two boron subnitrides, B13N2 and B50N2, have been measured as a function of temperature between 298 and 1273 K, and the corresponding thermal expansion coefficients have been determined. Thermal expansion of both…
We report thermal expansion measurements on Ca(Fe_(1-x)Co_x)_2As_2 single crystals with different thermal treatment, with samples chosen to represent four different ground states observed in this family. For all samples thermal expansion is…
We report anisotropic thermal expansion of the parent, AEFe2As2 (AE = Ba, Sr, and Ca), compounds. Above the structural/antiferromagnetic phase transition anisotropy of the thermal expansion coefficients is observed, with the coefficient…
The kinetics of sorption and subsequent desorption of argon gas by a C60 powder has been investigated in the temperature interval 58-290 K. The temperature dependence of the coefficients of Ar diffusion in fullerite has been obtained using…
Processing results of measurements of linear thermal expansion coefficients and linear thermal expansion of two brands of borosilicate glasses --- LK5 and Borofloat 33 --- are presented. The linear thermal expansion of glass samples have…
Heat capacity and anisotropic thermal expansion was measured for Ba(Fe_{1-x}Co_x)_2As_2 (x = 0, 0.038, 0.074) single crystals. Thermal expansion is anisotropic and, in tetragonal phase, is significantly higher along the c-axis. Previously…
This study examines the temperature-dependent evolution of the lattice constants for various CuAl2-type compounds, including NiZr2, (Co,Rh,Ir)Zr2, (Fe,Co,Rh,Ir)Zr2, and (Co,Ni,Cu,Rh,Ir)Zr2, in the pursuit of negative or zero thermal…
We present an NMR study of Na2C60 and K4C60, two compounds that are related by electron-hole symmetry in the C60 triply degenerate conduction band. In both systems, it is known that NMR spin-lattice relaxation rate (1/T1) measurements…
The thermal expansion of polycrystalline MgB2 from 5-300 K is studied using high-resolution capacitance dilatometry. The thermal expansivity exhibits a small jump of -5.8x10-8 K-1 at Tc (in accord with expectations from the Ehrenfest…
In a previous paper (cond-mat/0106554) we showed the existence of two new zero-temperature exponents (\lambda and \theta') in two dimensional Gaussian spin glasses. Here we introduce a novel low-temperature expansion for spin glasses…
The thermal expansion of pure and Ti-bearing fused silica was estimated using free energy minimization lattice dynamics calculations in the quasiharmonic approximation. While the calculations give the expected drop in the coefficient of…
Thermoelastic phenomena associated with orientational phase transition in solid C60 are considered. Coupling of the order parameter with elastic strain is analyzed in the Landau theory of phase transitions. Wide range of possible…
Melting is well understood in terms of the Lindemann criterion, essentially stating that crystalline materials melt when the thermal vibrations of their atoms become such vigorous that they shake themselves free of the binding forces.…
Analytical relations for the glass transition temperature, $T_g$, and the crystal melting temperature, $T_m$, are developed on the basis of nonaffine lattice dynamics. The proposed relations explain: (i) the seemingly universal factor of…
Recently, $\beta$-Te (atomically 2D tellurium) with rectangular crystal structure has been synthesized successfully on highly oriented pyrolytic graphite substrates by using molecular beam epitaxy. It has been found possessing remarkable…