Electron and phonon spectra dynamics and features of phase transitions in sodium at P=0-100 GPa

Electron and phonon spectra dynamics, as well as features of structural transitions and melting of sodium under pressure within range 0 to 100 GPa are investigated. Electron and phonon spectra of crystal sodium are calculated ab initio within the density functional theory by means of the LMTART-7 software package (Savrasov-Savrasov: 1992; Savrasov: 1996; Savrasov: 2004), allowing the fully potential method of linear muffin-tin orbitals. Using the Lindemann measure and the calculated phonon spectra the theoretical values of melting points corresponding to the experimental data (Gregoryanz, et al: 2005; Gregoryanz, et al: 2008) are obtained. Features of electron and phonon spectra dynamics in the melting curve maximum vicinity and within cI2->cI4 structural transition range are discussed.