Structure of supercooled liquid silicon

We report x-ray diffraction measurements of the structure factor S ( Q ) and the radial distribution function g ( r ) of levitated liquid silicon in the stable and supercooled states. Supercooling results in a sharpening of the first peak in S ( Q ) and shift to an 8% higher Q value, the appearance of a double shoulder on the high- r side of the first peak in g ( r ), a sharpening of the first peak in g ( r ) and a decrease in coordination number. These changes are consistent with a significantly enhanced degree of covalent bonding.