Synergistic and Diminutive Effects between Regium and Aerogen Bonds

• Published in: Chemphyschem Vol. 21; no. 21; pp. 2426 - 2431
• Main Authors: Wang, Ruijing, Wang, Zheng, Yu, Xuefang, Li, Qingzhong
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 03.11.2020
• Subjects: aerogen bond; Charge transfer; cooperativity; Copper; donor-acceptor systems; Gold; natural bond orbital; regium bond; Silver; regium bond; donor-acceptor systems; natural bond orbital; aerogen bond; cooperativity
• ISSN: 1439-4235; 1439-7641
• DOI: 10.1002/cphc.202000720

The aerogen bond is formed in complexes of HCN−XeF2O and C2H4−XeF2O. The lone pair on the N atom of HCN is a better electron donor in the aerogen bond than the π electron on the C=C bond of C2H4. The coinage substitution strengthens the aerogen bond in MCN−XeF2O (M=Cu, Ag, and Au) and its enhancing effect becomes larger in the Au<Cu<Ag pattern. The aerogen bond is further enhanced by the regium bond in C2H2−MCN−XeF2O and C2H4−MCN−XeF2O, but is weakened by the regium bond in MCN−C2H4−XeF2O and C2(CN)4−MCN−XeF2O. Simultaneously, the regium bond is also strengthened or weakened in these triads. The synergistic and diminutive effects between regium and aerogen bonds have been explained by means of charge transfer and electrostatic potentials. Synergistic or Diminutive? A synergistic effect is found in C2H2−MCN−XeF2O and C2H4−MCN−XeF2O. When the four H atoms of C2H4 are replaced with the −CN groups, this synergistic effect is changed into a diminutive one. This diminutive effect also occurs when C2H4 simultaneously forms a regium bond with MCN and an aerogen bond with XeF2O.