Structure And Potential Energy Function For Small Carbon Cluster And Its Ions And The New Vapor-Liquid Equilibrium For Hydrogen And Its Isotopes

The ground states and some excited ones for C2, C2+, C22+, C23+, C2-, C22- and C3, C3+, C3- molecules have been obtained by employing ab initio method and electronic configuration method. Using the general principles of Atomic and Molecular Reaction Statics (AMRS), we have studied the electronic states and dissociation limits. We have put forward a method that could be used to optimize the energy minimum point for diatomic molecules, especially for that the energy level and the nuclear equilibrium distances are very close.The Coulomb repulsion results in the potential maximum of doubly and triply diatomic ions. The perturbation effect of ionic charges is the cause of orbitally degenerate of diatomic ions.The force constants and dissociation energies of C3, C3+ and C3- have been calculated by ab initio method. Applying MEM to singly negative charged molecule C3-, we have deduced their analytical potential energy functions, plotted their potential energy surfaces.The symmetry and the stability of C42+ have been systematically studied by employing ab initio method and group theory. The Jahn-Teller effect and the perturbation of positive charges of Td configuration are obvious, and result in the non-degenerate state of the lowest symmetry.New equations of vapor-liquid equilibrium for H2 and its isotopes have been proposed, in which the reduced parameters are used to express the equilibrium, especially suitable for the calculation near the critical point. By using the proposed equations, the calculated values of saturated-vapor pressure and density are in quite good agreement with the values in the literatures.