Lattice dynamics properties of chalcopyrite ZnSnP₂: Density-functional calculations by using a linear response theory

We present a first-principles study of the structural, dielectric, and lattice dynamical properties for chalcopyrite semiconductor ZnSnP₂. The structural properties are calculated using a plane-wave pseudopotential method of density-functional theory. A linear response theory is used to derive Born effective charge tensors for each atom, dielectric constants in low and high frequency limits, and phonon frequencies. We calculate all zone-center phonon modes, identify Raman and infrared active modes, and report LO-TO splitting of the infrared modes. The results show an excellent agreement with experiment and propose several predictive behaviors.