Lattice location ofB12in aluminum and copper at 77 K

Polarized ${}_{}{}^{12}{}_{}{}^{}\mathrm{B}$ was produced in the reaction ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}(d,p){}_{}{}^{12}{}_{}{}^{}\mathrm{B}$ and recoiled into single-crystal samples of aluminum and copper. Resonance depolarization of the ${}_{}{}^{12}{}_{}{}^{}\mathrm{B}$ for the aluminum (copper) crystal oriented with each of its principal crystallographic directions in turn parallel to an externally applied holding field showed that 90-100% (76-100%) of the boron occupies the octahedral interstitial site.