1999/12/02 by V. N. Bogomolov, Bogomolov, V. N.
Chemistry · Earth and Planetary Sciences · Materials Science · Physics and Astronomy · #FOS: Physical sciences #High-pressure geophysics and materials #Inorganic Fluorides and Related Compounds #Organic and Molecular Conductors Research #Superconductivity (cond-mat.supr-con) #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.cond-mat/9912034
RevTeX, 2 eps figures, submitted to Phys. Rev. Lett
arxiv created 1999/12/02 · openalex publication_date 1999/12/02 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A simple model of the molecular crystal of N atoms as a statistical mixture in real space of NX atoms in excited and N(1-X) atoms in well localized ground state is considered. The phase coherence of the atomic wave functions is suppose to be absent. A bond energy of crystal is supposed to be a result of the pair interaction of NX excited atoms. These molecular type pair excitations do not interact one with another before the metallization, and do not contribute to the pressure. Nevertheless, the pressure of such kind of crystals is determined by the interatomic distances, and by the binding energy of pairs. The possibility of the insulator-superconductor transition of such a ``gas'' of NX/2 pairs, ``dissolved'' among N(1-X) atoms in ground state is discussed. This kind of transition is supposed to occur in the oxigen O2, in the sulphur S, and, possibly, in the xenon Xe crystals under pressure. The same kind of transition is likely to take place in HTSC materials, metal-ammonia and hydrogen-palladium solutions under normal conditions, due to similarity of some of their properties with the corresponding ones of molecular crystals.