Influence of chemical effect on the KP-to-K alpha X-ray intensity ratios of Ti, V, Cr and Fe in TiC, VC, CrB, CrB2 and FeB

K beta-to-K alpha X-ray intensity ratios of Ti, V, Cr and Fe have been meas ured in pure metals and in the compounds of TiC, VC, CrB, CrB2 and FeB foll owing excitation by 59.54 keV gamma-rays from a 200 mCi Am-241 point-source . Comparison of the measured K beta-to-K alpha X-ray intensity ratios with the multiconfiguration Dirac-Fock calculation indicates significant change in the 3d electron population of Ti in TIC and Cr in CrB and CrB2 from thei r pure metal values and almost no change for V in VC and Fe in FeB. In TIC we have found a transfer of 0.65 +/- 0.16 electrons from the 3d state of Ti whereas for CrB and CrB2 the 3d electron population of Cr increases by 0.6 0 +/- 0.30 and 0.75 +/- 0.30 electrons, respectively, over the pure metal v alue. Although our charge transfer result for TIC is closer to the predicti on of the APW band structure calculations no firm conclusion can be made fr om our VC result. Our result for the relative K beta-to-K alpha ratio of VC with respect to pure V does not agree with the previously reported experim ental result of Chang et al. (J. Phys. B: At. Mol. Opt. Phys. 27 (1994) 525 1). Our results for CrB and CrB2 predict transfer of electrons from boron t o 3d band of Cr in agreement with some of the earlier published results of magnetic and Hall effect measurements. (C) 1998 Elsevier Science B.V. All r ights reserved.