Calculation of the Thermodynamic Quantities for Cubic Gauche Nitrogen (cg-N)
Author:
YURTSEVEN Hamit1, AKAY Özge2
Affiliation:
1. MIDDLE EAST TECHNICAL UNIVERSITY, FACULTY OF ARTS AND SCIENCES, DEPARTMENT OF PHYSICS 2. MARMARA UNIVERSITY, FACULTY OF TECHNOLOGY
Abstract
This work aims to investigate the thermodynamic properties of the cubic gauge nitrogen (cg-N) by calculating the relevant thermodynamic quantities as a functions of temperature and pressure. The thermodynamic quantities of volume (V), thermal expansion (αp), isothermal compressibility (κT), bulk modulus(B), and the heat capacity (Cp) are calculated as a function of temperature at constants pressures (0, 35, 125, 250 GPa) for the cg-N structure. Also, the pressure dependences of V, κT, αp, Cp and γ (macroscopic Grüneisen parameter) are predicted at T= 295 K for this structure. This calculation is caried out by the thermodynamic relations using some literature data. From our calculations, we find that the κT, αp and also B exhibit anomalous behavior as the temperature lowers below about 100 K at constant pressures studied. This is an indication that cg-N transforms to a solid phase at low temperatures (below about 100 K). Experimental measurements can examine this prediction when available in the literature for the cg-N phase. Also, our predictions of the κT, αp, Cp and γ at various pressures (T= 295 K) can be examined experimentally for the cg-N phase. This calculation method can be applied to some other structures.
Publisher
International Centre for Applied Thermodynamics (ICAT)
Subject
General Engineering,Condensed Matter Physics
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