Hydrogen adsorption in C60 at pressures up to 2000 atm

Hydrogen adsorption isotherms of crystalline C60 were measured in the temperature interval from 223 to 573 K and under hydrogen pressure up to 2000 atm. Only the 573 K isotherm exhibited evidence for chemisorption starting from ∼800 atm. Hydrogen adsorption for isotherms measured below 473 K appeared to be not saturated even at 2000 atm. Maximum observed adsorption for these isotherms is almost the same and corresponds to 1.6–1.8 H2 molecules per C60. In contrast to experiments performed at lower pressure, presented data can not be explained only by adsorption of single H2 molecule in octahedral sites of C60 structure.