Polytype Dependence of Intralayer Bond Length in GaSe_1-xS_x Mixed Crystals (0.3 ≤x ≤0.4)

Abstract

The X-ray and Raman studies in GaSe 1- x S x indicate that the intralayer bond length between Ga-Ga atoms and that between Ga-chalcogen atoms are larger in the β-polytype than the respective lengths in γ, whereas the interlayer atomic distance between the chalcogen atoms in the γ-polytype may be equal to or larger than that in β. The lattice parameter, c , reduced to the 2H structure is longer in the β-polytype by 0.075±0.02 Å than in γ, while the parameter, a , is common for both polytypes within the accuracy of our measurements.