STRUCTURE OF LIQUID BORON

The structure factor S(Q) and the pair distribution function g(r) has been measured for liquid boron in the temperature range 2600-2000 K, e xtending over both the normal and supercooled liquid states. The bond length and coordination number of the first coordination shell are sim ilar to those reported for the crystalline and amorphous solid forms, but the second and third coordination shells are broader and shifted t o higher distances. The insulator-metal transition that takes place in boron upon melting is associated with a relatively small change in bo th volume and short-range order.