  Two-dimension (2D) semiconductor materials have attracted much attention and
research interest for their novel properties suitable for electronic and
optoelectronic applications. In this paper, we have proposed an idea in new 2D
materials design by using adjacent group elements to substitute half of the
atoms in the primitive configurations to form isoelectronic compounds. We have
successfully taken this idea on group V monolayers and have obtained many
unexplored Group IV-V-VI monolayer compounds: P2SiS, As2SiS, As2GeSe, Sb2GeSe,
Sb2SnTe, and Bi2SnTe. Relative formation energy calculations, phonon spectrum
calculations, as well as finite-temperature molecular dynamics simulations
confirm their stability and DFT calculations indicate that they are all
semiconductors. This idea broadens the scope of group V semiconductors and we
believe it can be extended to other type of 2D materials to obtain new
semiconductors with better properties for optoelectronic and electronic
applications.
