The energy resolution of an SSD (solid state detector) is better than that of scintillation and proportional counters by about one order of magnitude. By the use of this merit, the SSD has been used for X-ray energy-dispersive diffractometry. In this review, a standard system of the SSD diffractometer and its characterics including the energy resolution are described. Some applications are shown : measurements of anomalous scattering, anomalous scattering factors and a thermal vibration effect near the absorption edge. An MCSSD (multi-channel solid state detector) with a data collection system is described.
Electron diffraction in the gas phase is complementary to molecular spectroscopy in providing valuable information on the geometrical structures of polyatomic molecules. For all but the simplest molecules, more accurate structures can be obtained if these methods are used together in the analysis. The present article reviews the methods used for such a joint analysis. The effective use of the moments of inertia for several isotopic species for determining accurate average and equilibrium structures and constants representing bond-stretching anharmonicity is discussed, taking COCl2 molecule as an example.
Lithium clusters were prepared by evaporating lithium in argon at a pressure of 10-4-10-2 Torr and the mass numbers of these clusters containing up to 15 atoms and their relative abundances were measured by a quadrupole mass analyzer. In good vacuum lithium was detected as single, electrically neutral atoms. When argon was present, clusters composed of an even number of atoms were always detected. Li3 and Li5 were never detected. In the range Li7 to Li15 of clusters composed of an odd number of atoms were detected in smaller amounts than the case for neighbouring clusters containing an even number of atoms. A few experimental studies by means of various methods concerning clusters are reviewed briefly.