[Formula Presented] and [Formula Presented] x-ray emission lines of the [Formula Presented] transition metals

The [Formula Presented] and [Formula Presented] emission spectra of the [Formula Presented] transition metals Cr, Mn, Fe, Co, Ni, and Cu were measured, employing a single-crystal diffractometer optimized for minimal instrumental broadening. The high-accuracy diffractometer, and the interferometrically calibrated silicon crystal employed ensure absolute wavelengths in the metric scale to a sub-part-per-million accuracy. An accurate analytic representation of each line, obtained by a fit to a minimal set of Lorentzians, is presented. The absolute energies, linewidths, and indices of asymmetry, derived from the data, agree well with previous measurements. So do also the intensity ratios [Formula Presented] and [Formula Presented] which are, however, slightly, but consistently, higher than previous values. Possible origins for the observed [Formula Presented]-dependent trends are discussed.