The bulk properties of iron at the pressure and temperature conditions of E
arth's core were determined by a method that combines first-principles and
classical molecular dynamic simulations. The theory indicates that (i) the
iron melting temperature at inner-core boundary (ICB) pressure (330 gigapas
cals) is 5400 (+/-400) kelvin; (ii) Liquid iron at ICE conditions is about
6% denser than Earth's outer core; and (iii) the shear modulus of solid iro
n close to its melting tine is 140 gigapascals, consistent with the seismic
value for the inner core. These results reconcile melting temperature esti
mates based on sound velocity shock wave data with those based on diamond a
nvil cell experiments.