Study On The Molecular Face Of Hydrides And The Clusters Of Hydride

In this thesis, by means of molecular face theory, we studied the structure of the AH,, (A for the elements of the second and third period) and (LiH)n clusters; and explored the relationship of the Dpb of Y…H (Ydenotes the acceptorof hydrogen bond) and the strength of hydrogen bond for the HnA…HF dimers; Proposed a descriptor of hydrogen bond type; Studied the dynamic changes of the molecular face of H2O dimer and HF dimmer, Obtained a clear picture of dividing the interaction between molecules into the hydrogen bond interaction and van der Waals interaction, as well as proposed a scheme of calculating the first ionization energy of a dimmer. The details contents as follows:1. With MP2/6-311++G (3df,3pd) method (but for RbH with MP2/CEP-121G) optimized MHn and (LiH)n cluster geometry, and in the same calculated the theoretical level of the first ionization energy of molecular. the molecular AHn hydride were depicted by using the CISD/6-31+G** in MELD package and our in-house MF program with the basis set (except RbH use CISD/3-21G), describing the AHn (A for the second, the third period elements) of the molecular face. For ionic hydrides MH, their H atomic regions have expanded, whereas their metal atomic regions have shrunk. Discussion of the first ionization energy, polarizability (a) and the relationship between molecular contours. Through the molecular face of these molecules, to explore and understand these hydride and its structure and properties of clusters, providing an intuitive tool to explore and understand the structure and properties of these hydrides and their clusters.2. Study on the molecular face of HnA…HF dimer. The geometries of every HnA…HF dimmer was optimized by using MP2/6-311++G (3df,3pd) method. The potential acting on an electron with a molecule (PAEM) was calculated in terms of the CISD/6-31+G** in the ab initio MELD package and our in-house PAEM program. The PAEM along the Y…Hwas displayed and studied for every dimer, in which Y and H denote the atoms of the acceptor and donor of HB, respectively. It found that there is a saddle point of PAEM between Y and H atoms. Dpb denotes the value of PAEM at the saddle point.Δd denotes the difference between d2 and d1 in which d1 denotes the distance between the electron and Y and d2 denotes the distance between the electron and H. Dpb is a physical quantity of charactering the strength of HB, andΔd is a descriptor of judging the type of HB.3. The study on the dynamic change of the molecular face of H2O dimer and HF dimmer.In dynamic change of molecular face of H2O dimers and HF dimers molecular, explored the essence of interact between molecules. The dynamic change of the molecular face, two molecules face showed a very interesting picture. When two molecules apart is farther, every molecule to maintain their own respective molecular face, when two atoms in contact, each molecule has obvious changes, approaching to a stable structure, gradually. Be in molecular contact with before the interaction between molecules are mainly van der Waals interaction, the contact point, the molecular interactions with covalent bonding. From two molecules of the charge distribution, we also see this. This study is the nature of the interaction between molecules, providing an intuitive understanding.