Gaseous germyl cations: A theoretical investigation on the structure, properties, and mechanism of formation of FnGe(OH)3-n+ and FnGe(NH2)3-n+ (n = 0-2)

► The germyl cations FnGe(OH)3-n+ and FnGe(NH2)3-n+ (n = 0-2) are covalent species. ► The bond distances decrease by increasing the electronegativity of the adjacent substituents. ► The thermochemical stabilities increase by replacing F with OH and NH2. ► The Lewis acidities decrease by replacing F with OH and NH2. ► The cations form from GeF3+ and H2O or NH3 by mechanisms described by triple-well energy surfaces.