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. (paper)