Information on the energy band gaps, the lattice parameter and the lattice matching to available substrates is a prerequisite for many practical applications. A pseudopotential plane-wave method, as implemented in the ABINIT code, is used to the GaPxAsySb1−x−y quaternary alloy lattice matched to GaAs and InP substrates to predict their energy band gaps, elastic constants and lattice dynamic properties. The ranges of compositions for which the alloy is lattice-matched to GaAs and InP are determined. A very good agreement is obtained between the calculated values and the available experimental data of GaAs and GaAs0.5Sb0.5 parents. The compositional dependence of direct and indirect band gaps has been investigated. Note that a phase transition occurred at As composition of 0.018 and 0.576 for GaPxAsySb1−x−y within InP and GaAs substrates. The static and high-frequency dielectric constants and refractive index are indeed inversely proportional (proportional) to the fundamental band gap for GaPxAsySb1−x−y within InP (GaAs) substrates. We study the variation of elastic constants, the optical phonon frequencies (ωTO and ωLO) and the Born effective charge Z* with As concentration.Podaci o energijskim procijepima, parametrima rešetke i prileživanju na dostupne podloge je preduvjet mnogin primjenama. Rabimo metodu ravnih valova s pseudopotencijalom, primijenjenu u programu ABINIT, da bismo predvidjeli procijepe energijskih vrpci, elastične konstante i dinamička svojstva rešetaka legure GaPxAsySb1−x−y s četiri sastavnice, priležne na GaAs i InP podloge. Odredili smo područja sastava za koja rešetke priliježu na GaAs i InP. Postigli smo vrlo dobar sklad izračunatih vrijednosti s eksperimentalnim podacima za polazne legure GaAs i GaAs0.5Sb0.5. Istražili smo ovisnost izravnih i neizravnih procijepa vrpci o sastavu. Opaža se pojava faznog prijelaza za sadržaj As od 0.018 i 0.576 u GaPxAsySb1−x−y na InP i GaAs podlogama. Statičke i visokofrekventne dielektrične konstante te indeks loma su obrnuto razmjerni (razmjerni) širini osnovnog procijepa vrpci u GaPxAsySb1−x−y na InP and GaAs podlogama. Proučavamo promjene elastičnih konstanti, optičkih fononskih frekvencija (ωTO i ωLO) te Bornovog efektivnog naboja Z ∗ u ovisnosti o sadržaju As
