To extend our knowledge of the germanium-phosphorus triple bond, the isomerization reactions of singlet XGeP (i.e., XGedropP --> TS --> Gedouble bondPX; Xdouble bondH, Li, BeH, BH2, CH3, SiH3, NH2, PH2, OH, SH, F, and Cl) were investigated using B3LYP and CCSD(T) calculations. It is found that electronegative and pi-electron-donating substituents (X) can stabilize the XGedropp triply bonded species in a kinetic sense, although germanium is less reluctant to form Gedouble bondP doubly bonded than Gedropp triply bonded compounds.