The Mossbauer spectra of some slag samples were measured at room temperature. The spectra are fitted with three quadrupole split doublets which refer to Fe2+and Fe3+ with different micro-environments. According to the Mb s sbauer spectrum data of FexO in literatures

the main substance in the slag samples is considered to be FexO. An X-ray diffraction analysis gave the same result. The relative content of Fe2+ and Fe3+ ions in the slag

calculated according to the corresponding sub-spectra area ratio

is 85% and 15% respectively for some different samples. The SCF MS- Xα method was used to compute charge densities and electric field gradients at nuclear site. An agreement was obtained between the calculated charge densities and the measured isomer shifts. However

the calculation should be improved for a better consistence between the calculated electric field gradients and the measured quadrupole splits.