Global three-dimensional potential energy surfaces of H2S from the ab initio effective valence shell Hamiltonian method

Stevens, Jonathan E.; Chaudhuri, Rajat K.; Freed, Karl F.
November 1996
Journal of Chemical Physics;11/15/1996, Vol. 105 Issue 19, p8754
Academic Journal
The correlated, size extensive ab initio effective valence shell Hamiltonian (HV) method is used to compute three-dimensional potential energy surfaces for the ground and several excited electronic states of the H2S molecule. A single calculation of the HV simultaneously generates all states of interest as well as ionization potentials. Particular emphasis is placed on the two lowest 1 1A″ excited surfaces (one valencelike and the other Rydberg-type) that are involved in recent experiments probing nonadiabatic photodissociation processes. Supplementary effective operator calculations generate three-dimensional surfaces of dipole moments and transition dipole matrix elements, but emphasis is placed on the transition dipoles relevant to the dissociation process. Comparisons to both experiment and previous calculations for this system support the ability of multireference perturbation methods to describe global potential energy surfaces for open shell systems. We discuss the implication of our calculations for interpreting and reproducing experimental observations of the dissociation dynamics. © 1996 American Institute of Physics.


Related Articles

  • Ab initio study of the molecules BC and B2C. Martin, Jan M. L.; Taylor, Peter R. // Journal of Chemical Physics;6/15/1994, Vol. 100 Issue 12, p9002 

    The potential energy surface for the B2C molecule and the potential energy curve for the ground state of BC have been investigated using full-valence complete active space SCF (CASSCF), augmented coupled cluster [CCSD(T)] and multireference treatments. The ground state of B2C is an...

  • An adjusted global potential surface for HCN based on rigorous vibrational calculations. Gazdy, Bela; Bowman, Joel M. // Journal of Chemical Physics;11/1/1991, Vol. 95 Issue 9, p6309 

    We report extensive trial and error modifications of the Murrell–Carter–Halonen potential surface for HCN to improve agreement with experiments on highly excited stretching and bending states. The vibrational calculations make use of an exact Hamiltonian for nonrotating HCN and use...

  • Excited state fragments following molecular ionization and dissociation in strong fields. Nibarger, John P.; Li, Ming; Menon, Saipriya; Gibson, George N. // AIP Conference Proceedings;2000, Vol. 525 Issue 1, p483 

    We have observed for the first time that charge asymmetric dissociation in diatomic molecules leaves one of the fragments in an electronically excited state. Using a new double pulse technique, we determine the state of the post dissociation fragments. For example, we observed the reaction I[sub...

  • Molecular beam resonant two-photon ionization study of caffeine and its hydrated clusters. Kim, Doory; Hyung Min Kim; Key Young Yang; Seong Keun Kim; Nam Joon Kim // Journal of Chemical Physics;4/7/2008, Vol. 128 Issue 13, p134310 

    We investigated electronically excited states of caffeine and its 1:1 complex with water by using resonant two-photon ionization (R2PI) and UV-UV hole-burning techniques. Strong vibronic coupling between a pair of close-lying π-π* and n-π* transitions is proposed to be responsible...

  • Lie algebraic approach to potential energy surface for symmetric triatomic molecules. Shiliang Ding; Yujun Zheng // Journal of Chemical Physics;9/8/1999, Vol. 111 Issue 10, p4466 

    Derives the expression of the potential energy surface containing information about the bending motion of triatomic molecules. Use of the semiclassical limit of the algebraic Hamiltonian; Force constants obtained.

  • Application of the effective valence shell Hamiltonian method to accurate estimation of.... Chaudhuri, Rajat K.; Das, B.P. // Journal of Chemical Physics;2/8/1998, Vol. 108 Issue 6, p2556 

    Examines the application of valence shell Hamiltonian method to estimate the excitation energies and oscillator strengths of magnesium-like ions. Significance of size extensibility for potential energy surfaces; Relationship between basis set size and polarization; Dependence of oscillator...

  • Multi-reference Fock space coupled-cluster method in the intermediate Hamiltonian formulation for potential energy surfaces. Musiał, Monika; Bartlett, Rodney J. // Journal of Chemical Physics;7/28/2011, Vol. 135 Issue 4, p044121 

    The effective and intermediate Hamiltonian multi-reference coupled-cluster (CC) method with singles and doubles for the doubly ionized (0,2) sector of Fock space (FS) is formulated and implemented. The intermediate Hamiltonian realization of the (0,2) FS problem provides a robust computational...

  • The effect of ionization on the global minima of small and medium sized silicon and magnesium clusters. De, Sandip; Ghasemi, S. Alireza; Willand, Alexander; Genovese, Luigi; Kanhere, Dilip; Goedecker, Stefan // Journal of Chemical Physics;3/28/2011, Vol. 134 Issue 12, p124302 

    We re-examine the question of whether the geometrical ground state of neutral and ionized clusters are identical. Using a well defined criterion for being 'identical' together, the extensive sampling methods on a potential energy surface calculated by density functional theory, we show that the...

  • Excited states of the water molecule: Analysis of the valence and Rydberg character. Rubio, Mercedes; Serrano-Andrés, Luis; Merchán, Manuela // Journal of Chemical Physics;3/14/2008, Vol. 128 Issue 10, p104305 

    The excited states of the water molecule have been analyzed by using the extended quantum-chemical multistate CASPT2 method, namely, MS-CASPT2, in conjunction with large one-electron basis sets of atomic natural orbital type. The study includes 13 singlet and triplet excited states, both valence...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics