Ab-initio study of phase transitions in NaNO2 crystals based on band structure calculations

► Ab-initio simulation of band structure and phase transitions in NaNO2 have been done. ► Paraelectric phase of NaNO2 is represented by the double ferroelectric unit cell. ► The energy vs. volume dependences E(V) for these phases possess two crossing points. ► The enthalpy vs. pressure dependences H(P) agree with experimental reference results. ► Dependences H(P) for P ; 0 are useful for study of thermally stimulated transition.