DIFFRACTIVE SCATTERING OF HYDROGEN DIMERS FROM LIF(001)

The weakly bound hydrogen dimer has been detected in diffraction from LiF(001) along the [100] direction. The incident dimer energy is 48 meV and the crystal surface temperature is 150 K. The data are analyzed with a simple eikonal clastic scattering calculation and inelastic phonon scattering attenuation is estimated with a measured Debye-Waller factor. These calculations suggest that at least 5% of the dimers survive fragmentation. The well-defined first-order diffraction peak has an intensity of order 5 x 10(14) dimers/sec str which could be useful for further beam studies.