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arXiv · 2606.07267

Peculiarities Of Phase States In N2O-CO2 Cryoalloys According To Electron Diffraction Data

A. A. Solodovnik·O. P. Konotop
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Abstract

The structural characteristics of n2o-co2 alloys have been studied using transmission electron diffraction (THEED) across the entire range of their mutual concentrations at temperatures of 5 K and 65 K. The ranges in which regular solutions exist and intervals of alloy phase separation have been identified using the dependence of lattice parameters on composition and profile analysis of the diffraction pattern intensity distribution. It was found that maximum solubility values are up to 11 mol.% CO2 in the N2O matrix and up to 30 mol.% n2o in solid co2 at 65 K. The solubility limits for the components at 5 K are less 20 mol.% co2 in crystalline n2o and less than 35 mol.% n2o in a co2 crystal lattice. It was established that the character of n2o-co2 alloy separation corresponds to the mechanism of spinodal decomposition. The relative excess volumes that pertain to the admixture were determined for the CO2 impurity in solid n2o and for n2o impurity in co2 crystal. Conclusions regarding the character of n2o-co2 phase diagram have been made.

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A. A. Solodovnik, O. P. Konotop. 2026-06-05. Peculiarities Of Phase States In N2O-CO2 Cryoalloys According To Electron Diffraction Data. https://arxiv.org/abs/2606.07267

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