material(e.g. Ge111, Ge444) Notice, that the Ge222 configuration is forbidden due to diffraction rules stating, that all allowed reflections must be with all odd or all even Miller indices that, combined, result in , where is the order of reflection. Elemental analysis lines The spectral lines used for elemental analysis of chemicals are selected on the basis of intensity, accessibility by the instrument, and lack of line overlaps. Typical lines used, and their wavelengths, are as follows: Other lines are often used, depending on the type of sample and equipment available. Structural analysis lines X-ray Diffraction(XRD) is still the most used method for structural analysis of chemical compounds. Yet, with increasing detail on the relation of -line spectra and the surrounding chemical environment of the ionized metal atom, measurements of the so-called Valence-to-Core(V2C) energy region become more and more viable. Scientists noted that after ionization of 3d-transition metal-atom the -line intensities and energies shift with oxidation state of the metal and with the species of ligand(s). The importance of spin-states in a compound tend to make big differences in this kind of measurement, too.: This means, that by intense study of these spectral lines, one can obtain several crucial pieces of information from a sample. Especially, if there are references that have been studied in detail and can be used to make out differences. The information collected from this kind of measurement include: Oxidation State of Central Metal Atom in a Compound(shifts of -mainline in low-spin complexes) Spin-States of Transition Metal Complexes(general shape of - and -mainlines) Structural Electronic Configuration around Central Metal Atom(determine intensity, broadening, tailing and piloting of - and -lines) These kinds of measurements are mostly done at synchrotron facilities, although a number of so-called "In-Lab"-Spectrometers have been developed and used for pre-beamtime (time at a synchrotron) measurements. Detectors Detectors used for wavelength dispersive spectrometry need to have high pulse processing speeds in order to cope with the very high photon count rates that can be obtained. In addition, they need sufficient energy resolution to allow filtering-out of background noise and spurious photons from the primary beam or from crystal fluorescence. There are four common types of detector: gas flow proportional counters sealed gas detectors scintillation counters semiconductor detectors Gas flow proportional counters are used mainly for detection of longer wavelengths. Gas flows through it continuously. Where there are multiple detectors, the gas is passed through them