Origin of selenium-gold interaction in F2CSe . . . AuY (Y = CN, F, Cl, Br, OH, and CH3): Synergistic effects.

Selenium-gold interaction plays an important role in crystal materials, molecular self-assembly, and pharmacochemistry involving gold. In this paper, we unveiled the mechanism and nature of selenium-gold interaction by studying complexes F₂CSe...AuY (Y = CN, F, Cl, Br, OH, and CH₃). The results showed that the formation of selenium-gold interaction is mainly attributed to the charge transfer from the lone pair of Se atom to the Au--Y anti-bonding orbital. Energy decomposition analysis indicated that the polarization energy is nearly equivalent to or exceeds the electrostatic term in the selenium-gold interaction. Interestingly, the chalcogen-gold interaction becomes stronger with the increase of chalcogen atomic mass in F₂CX...AuCN (X = O, S, Se, and Te). The cyclic ternary complexes are formed with the introduction of NH₃ into F₂CSe...AuY, in which selenium-gold interaction is weakened and selenium-nitrogen interaction is strengthened due to the synergistic effects. [ABSTRACT FROM AUTHOR]