Abstract:
Search for e cient materials for application in the elds of optoelectronics and photovoltaics
are active areas of research across the world. The potential of compounds such as K3Cu3P2 is
not yet fully realized. Therefore, we perform the ab initio studies based on density functional
theory to investigate the structural, electronic, elastic, and optical properties of K3Cu3P2. Ground
state properties were computed in three di erent scenarios, i.e: with spin-orbit coupling (SOC),
without spin-orbit coupling, and with Hubbard U parameter. Direct electronic bandgaps of 1.338 eV,
1.323 eV and 1.673 eV were obtained for K3Cu3P2 without SOC, K3Cu3P2 with SOC and K3Cu3P2
with Hubbard U respectively. In all the cases, Cu-d orbitals were dominant at the top of the valence
band. The e ect of SOC on the K3Cu3P2 computed lattice constant and bandgap was insigni cant.
The mechanical stability test indicated that K3Cu3P2 is mechanically stable at zero pressure. The
optical band gap was found to increase by 0.635 eV when Hubbard U was taken into consideration.
Generally, the inclusion of the Hubbard U parameter in density functional theory improves the
predictions of the bandgap and optical properties.
