  Based on extensive evolutionary algorithm driven structural search, we
propose a new diphosphorus trisulfide (P2S3) 2D crystal, which is dynamically,
thermally and chemically stable as confirmed by the computed phonon spectrum
and ab initio molecular dynamics simulations. This 2D crystalline phase of P2S3
corresponds to the global minimum in the Born-Oppenheimer surface of the
phosphorus sulfide monolayers with 2:3 stoichiometries. It is a wide band gap
(4.55 eV) semiconductor with P-S {\sigma} bonds. The electronic properties of
P2S3 structure can be modulated by stacking into multilayer P2S3 structures,
forming P2S3 nanoribbons or rolling into P2S3 nanotubes, expanding its
potential applications for the emerging field of 2D electronics.
