Calculations using the self-consistent unrestricted Hartree-Fock-Rooth
an method are carried out in the MNDO approximation for a cluster of 3
5 host atoms of cubic SiC with a boron impurity. The equilibrium geome
try and the hyperfine and quadrupole constants are obtained and compar
ed with experimental values. The computed parameters reveal the main f
eatures of boron impurities in SiC.