Calculation of the Thermodynamic Quantities for Cubic Gauche Nitrogen (cg-N)

Creative Commons License

Yurtseven H., Akay O.

INTERNATIONAL JOURNAL OF THERMODYNAMICS, vol.25, no.3, pp.32-39, 2022 (ESCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 25 Issue: 3
  • Publication Date: 2022
  • Doi Number: 10.5541/ijot.1085553
  • Journal Name: INTERNATIONAL JOURNAL OF THERMODYNAMICS
  • Journal Indexes: Emerging Sources Citation Index (ESCI), Scopus, Applied Science & Technology Source, Compendex, Computer & Applied Sciences
  • Page Numbers: pp.32-39
  • Keywords: Thermodynamic quantities, cubic gauche nitrogen, macroscopic Gruneisen parameter, MOLECULAR NITROGEN, PHASE, TRANSFORMATION, TRANSITIONS, FORM, GPA
  • Middle East Technical University Affiliated: Yes

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 (alpha p), isothermal compressibility (kappa T), 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, kappa T, alpha p, Cp and gamma (macroscopic Gruneisen 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 kappa T, alpha p 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 kappa T, alpha p, Cp and gamma 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.