The Study Of The Theory Of The New Type Non Covalent Interaction Between Silver Key

With the experiment technology and theoretical calculation softwareimprovement, more and moore new non-covalent interaction have been observed. Forexample, CH3and HX （X = F, Cl, Br）, H₂O, CH4, HCN and single electronichydrogen bond between HCN interaction; He-LiH and C3-X （X = He, Ar） this kind ofinert gas interaction; M（CO）5YH3metal coordination function, and so on. These newnon-covalent interactions improve the understanding for them. Hense, for newnon-covalent interaction, the investigation on the nature and characteristics is verymeaningful and valuable. Recently, Legon group experimentally confirmed geometricstructures of H₂O…AgCl and H₂S…AgCl. They found that the geometric structuresbetween H₂O/ H₂S…AgCl are similar and that there exits direction similar tohydrogen bonding H₂O/H₂S... HCl and halogen bonding H₂O/H₂S…ClF. On the basisof the concept of hydrogen bonding and halogen bonding, they put forward that thereis a new kind of non-covalen interaction between H₂O/H₂S and AgCl, namely silverbonding. For silver bonding, whether there really exits and if it is a new bonding,what the characteristics of the silver bonding and what the formation mechanism is. Inthe third chapter, we have carried out a theoretical research for H₂O…AgCl andH₂S…AgCl complexes. In order to compared with corresponding hydrogen bondingH₂O/H₂S... HCl and halogen bonding H₂O/H₂S... ClF, we have calculated thesehydrogen bonding and halogen bonding complexes. The results showed that thereexits non-covalent interaction between H₂O and AgCl, also exits in H₂S…AgCl. andthat silver bonding is blue-shifted and tended to ion properties; The interactionenergies of the silver bonding is higher than the corresponding hydrogen bonding andhalogen bonding. This silver bonding was also a kind of electrostatic effect. Thetopological properties analysis of electron density and Laplacian are not in hydrogenbonding and halogen bonding range. In order to further expand the silver bonding, wein the fourth chapter have used the same theoretical calculation method to research thenon-covalent interaction between AgX and HC≡CH. They formПtype of silverbonding and complex geometries are T type . This kind ofПtype of silver bonding in the infrared spectra also display blue-shifted characteristics. In the fifth chapter, wehave characterised silver bonding between AgX and epoxy ethane, and studied itsformation mechanism. There also exist silver bonding between AgX and epoxy ethane,and in the infrared spectra they show blue-shifted. The topological analysis of AIMalso reveal that the property of this silver bonding tends to ion properties. Theanalysis of NBO of this silver bonding show that the formation mechanism is both ofthe hyperconjugative interaction （charge transfer） from a lone pair of the protonacceptor （Y） to the antibondingσ* orbital of the proton donating bond （X-H） andorbit rehybridization. Orbit rehybridization is accord with Bent’s rule. The silverbonding occurred blue-shifted because the influence of orbit rehybridization outweighsthat of hyperconjugative.