Low Temperature Physics: 39, 427 (2013); https://doi.org/10.1063/1.4807044 (3 pages)
Физика Низких Температур: Том 39, Выпуск 5 (Май 2013), c. 552-555 ( к оглавлению , назад )
Melting line of polymeric nitrogen
Thermophysics Department, Odessa State Academy of Refrigeration, 1/3 Dvoryanskaya Str., Odessa 65082, Ukraine
Received December 5, 2012
We made an attempt to predict location of the melting line of polymeric nitrogen using two equations for Helmholtz free energy: proposed earlier for cubic gauche-structure and developed recently for liquid polymer-ized nitrogen. The P–T relation, orthobaric densities and latent heat of melting were determined using a standard double tangent construction. The estimated melting temperature decreases with increasing pressure, alike the temperature of molecular–nonmolecular transition in solid. We discuss the possibility of a triple point (solid–molecular fluid–polymeric fluid) at ~ 80 GPa and observed maximum of melting temperature of nitrogen.
PACS: 05.70.Ce Thermodynamic functions and equations of state;
Key words: solid nitrogen, polymerization, phase transition, equation of stare.