The method of ab initio molecular dynamics, based on finite temperature density functional theory, is used to simulate laser heating of crystal silicon. We have found that a high concentration of excited electrons dramatically weakens the covalent bond. As a result, the system undergoes a melting transition to a metallic state. In contrast to ordinary liquid silicon, the new liquid is characterized by a high coordination number and a strong reduction of covalent bonding effects.

Phys. Rev. Lett.

Silvestrelli, P. L., Alavi, A., Parrinello, M., & Frenkel, D. (1996). Ab initio molecular dynamics simulation of laser melting of silicon. Phys.Rev.Lett., 77, 3149–3152.