Ortho and para O-H2 complexes in silicon -: art. no. 245208

Interstitial H-2 becomes bound to interstitial O in silicon, forming an O-H-2 complex. Infrared absorption experiments performed for the O-HD complex in Si reveal HD vibrational lines that appear at elevated temperature (T>10 K). These lines and their properties lead to the conclusion that the H-2 molecule in the O-H-2 complex is a nearly free rotor. Two near-lying lines seen for the oxygen mode of the O-H-2 complex are attributed to the ortho and para O-H-2 complexes. The ortho and para states of the O-H-2 complex also give rise to H-2 vibrational lines with distinct properties. These results may be understood in terms of a hindered-rotor model for the hydrogen molecule.