Explosive crystallization mechanism of ultradisperse amorphous films

The explosive crystallization of germanium ultradisperse amorphous films is studied experimentally. We show that crystallization may be initiated by local heating at the small film thickness but it realizes spontaneously at the large ones. The fractal pattern of the crystallized phase is discovered that is inherent in the phenomena of diffusion limited aggregation. It is shown that in contrast to the ordinary crystallization mode the explosive one is connected with the instability which is caused by the self-heating. A transition from the first mechanism to the second one is modelled by Lorenz system. The process of explosive crystallization is represented on the basis of the self-organized criticality conception. The front movement is described as the effective diffusion in the ultrametric space of hierarchically subordinated avalanches, corresponding to the explosive crystallization of elementary volumes of ultradisperse powder. The expressions for the stationary crystallization heat distribution and the steady-state heat current are obtained. The heat needed for initiation of the explosive crystallization is obtained as a function of the thermometric conductivity. The time dependence of the spontaneous crystallization probability in a thin films is examined.Comment: 22 pages, 5 figures, LaTe

Counting function fluctuations and extreme value threshold in multifractal patterns: the case study of an ideal 1/f1/f noise

To understand the sample-to-sample fluctuations in disorder-generated multifractal patterns we investigate analytically as well as numerically the statistics of high values of the simplest model - the ideal periodic $1/f$ Gaussian noise. By employing the thermodynamic formalism we predict the characteristic scale and the precise scaling form of the distribution of number of points above a given level. We demonstrate that the powerlaw forward tail of the probability density, with exponent controlled by the level, results in an important difference between the mean and the typical values of the counting function. This can be further used to determine the typical threshold $x_m$ of extreme values in the pattern which turns out to be given by $x_m^{(typ)}=2-c\ln{\ln{M}}/\ln{M}$ with $c=3/2$. Such observation provides a rather compelling explanation of the mechanism behind universality of $c$. Revealed mechanisms are conjectured to retain their qualitative validity for a broad class of disorder-generated multifractal fields. In particular, we predict that the typical value of the maximum $p_{max}$ of intensity is to be given by $-\ln{p_{max}} = \alpha_{-}\ln{M} + \frac{3}{2f'(\alpha_{-})}\ln{\ln{M}} + O(1)$, where $f(\alpha)$ is the corresponding singularity spectrum vanishing at $\alpha=\alpha_{-}>0$. For the $1/f$ noise we also derive exact as well as well-controlled approximate formulas for the mean and the variance of the counting function without recourse to the thermodynamic formalism.Comment: 28 pages; 7 figures, published version with a few misprints corrected, editing done and references adde

Program Moment of inertia

The program calculates the moments of inertia of the molecules Ix, Iy and Iz relative to the x, y and z axes (the axis of rotation with the minimum moment of inertia is taken as the x axis, the y and z axes are perpendicular to it and to each other). The coordinates for the atoms from the XYZ file are used as data for the calculation

Program Moment of inertia

The program calculates the moments of inertia of the molecules Ix, Iy and Iz relative to the x, y and z axes (the axis of rotation with the minimum moment of inertia is taken as the x axis, the y and z axes are perpendicular to it and to each other). The coordinates for the atoms from the XYZ file are used as data for the calculation

Data for: Using the molecular rotational motion concept within the framework of the "structure-property" problem to predict the volume expansion coefficients and densities of liquids

1) To calculate the average volume expansion coefficient reference data of liquid densities in the range of 20–50 °C were used, and the entropy was calculated for the middle of the specified interval (35 °C).2) Calculations of the moments of inertia were made as follows. Initially, for a conformer (if a conformational isomerism was possible for the compound) with minimal energy, a nonempirical calculation of optimized atomic coordinates was performed using the GAMESS software package (ver. 2018-R1-pgi-mkl, the Hartree-Fock method, basis 6-31G*), which was then used to calculate moments of inertia in the program "Moments of inertia" written specially for this purpose. The correctness of the results obtained was verified (for those compounds for which it was possible) by comparison with the database of computational chemistry and comparative tests of the National Institute of Standards and Technology (NIST).THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

On The Question Of The Relationship Between The Rotational Motion Of Molecules And The Alternation Of Properties In Homological Series. Additional materials for the article

The data contains: 1) Calculation of the optimized coordinates of n-alkanes by the PBE method using the 6-311++G(2d,2p) basis set; 2) Calculation of the moments of inertia of n-alkanes using optimized coordinates; 3) Theoretical calculation of moments of inertia for carbon chains