IR and NMR properties of N-base:PH₂F:BeX₂ ternary and corresponding binary complexes stabilised by pnicogen and beryllium bonds

Ab initio MP2/aug’-cc-pVTZ calculations have been performed to determine selected stretching frequencies and chemical shieldings for ternary complexes N-base:PH2F:BeX2 the corresponding binary complexes, with NH3, H2C=NH, HCN as nitrogen bases H, F, Cl substituents X. Be-F P-F depend on distances, respectively, while P F N-P respectively. The graph of versus distance bears a remarkable resemblance that same distance. EOM-CCSD spin–spin coupling constants also evaluated complexes. 1pJ(N-P) is negative at longer distances found in which N … bond traditional pnicogen some phosphorous-shared character, gains phosphorus-shared character continues decrease, then becomes phosphorous-transferred ion-pair shorter NH3 H2C=NH. 1J(P-F) values are large HCN, but increase become positive H2C=NH increases.