Zobrazeno 1 - 10
of 166
pro vyhledávání: '"Jan Almlöf"'
Publikováno v:
International Journal of Quantum Chemistry. 36:345-354
The requirements for very accurate ab initio quantum chemical prediction of dissociation energies are examined using a detailed investigation of the nitrogen molecule. Although agreement with experiment to within 1 kcal/mol is not achieved even with
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::3f316103573082193d2a06699689d657
https://doi.org/10.1002/qua.560360838
https://doi.org/10.1002/qua.560360838
Publikováno v:
Theoretical Chemistry Accounts: Theory, Computation, and Modeling (Theoretica Chimica Acta). 99:1-7
Relativistic two-electron operators obtained by the Douglas-Kroll transformation contain p-dependent kinematic prefactors which are not present in the corresponding Breit-Pauli operators. These factors are usually calculated using a resolution of the
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::cf294191e5811ced51a16567d83e9715
https://doi.org/10.1007/s002140050296
https://doi.org/10.1007/s002140050296
Publikováno v:
International Journal of Quantum Chemistry. 68:53-64
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::39056696a767f06968bd9973d180ce86
https://doi.org/10.1002/(sici)1097-461x(1998)68:1<53::aid-qua2>3.0.co
https://doi.org/10.1002/(sici)1097-461x(1998)68:1<53::aid-qua2>3.0.co
Autor:
Jan Almlöf
Publikováno v:
Theoretical Chemistry Accounts: Theory, Computation, and Modeling (Theoretica Chimica Acta). 97:10-13
A method is proposed for efficient use of molecular symmetry in the evaluation of two-electron integrals. This provides a means of avoiding the recalculation of symmetry-redundant integrals, and of symmetry-blocking matrices and supermatrices without
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::4ce2e14d301a718dc1bd0b14b958bd8c
https://doi.org/10.1007/s002140050233
https://doi.org/10.1007/s002140050233
Autor:
Jeppe Olsen, Jan Almlöf, Trond Saue, Odd Gropen, Merethe Sjo, Trygve Helgaker, voll, Hilde Fagerli
Publikováno v:
The Journal of Chemical Physics. 107:5496-5501
The lower states of the PdH molecule have been studied with different relativistic methods. At the spin-free level, relativistic effects are shown to be crucial for a proper description of the molecule. PdH is shown to be a single-configuration molec
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::6cdabbda8875682e22eff0a5da4063b5
https://doi.org/10.1063/1.474254
https://doi.org/10.1063/1.474254
Autor:
Jan Almlöf, I. Røeggen
Publikováno v:
Journal of Molecular Structure: THEOCHEM. 388:331-337
The three-body potential for the ground state of the helium trimer is determined by an extended geminal model. The model includes triple pair correlation terms calculated by the coupled-cluster model CCSD(TQ). The basis set for the calculation is an
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::13b56d81ac5bfe2d0d32daeaceb6a431
https://doi.org/10.1016/s0166-1280(96)80047-9
https://doi.org/10.1016/s0166-1280(96)80047-9
Autor:
Deborah J. Hankinson, Jan Almlöf
Publikováno v:
Journal of Molecular Structure: THEOCHEM. 388:245-256
Model compounds designed to simulate graphite and lithium intercalated graphite (LIG) have been investigated in ab initio calculations at the Hartree-Fock and Second-Order Moller-Plesset levels of theory. Several cluster models were used in attempts
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::279215bba20446e0513f2e08186d9acc
https://doi.org/10.1016/s0166-1280(96)80038-8
https://doi.org/10.1016/s0166-1280(96)80038-8
Autor:
Jan Almlöf, Marianna Fanti
Publikováno v:
Journal of Molecular Structure: THEOCHEM. 388:305-313
The dipole axis diagonal components of static polarizability α, first-order hyperpolarizability β and second-order hyperpolarizability γ of a series of push-pull polyphenyls are calculated via a simplified sum over states (SOS) technique based on
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::66f0b8d99e54f137879cbb765bc9fadd
https://doi.org/10.1016/s0166-1280(96)80044-3
https://doi.org/10.1016/s0166-1280(96)80044-3
Autor:
Jan Almlöf, Yu Cheng Zheng
Publikováno v:
Journal of Molecular Structure: THEOCHEM. 388:277-284
We have previously developed a grid-free approach to implement local density functionals based entirely on matrix representations of operators known from conventional electronic structure methods (Y.C. Zheng and J. Almlof, Chem. Phys. Lett., 214 (199
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::d66698daa8d8d72e5dbecb145fe6e025
https://doi.org/10.1016/s0166-1280(96)80040-6
https://doi.org/10.1016/s0166-1280(96)80040-6
Publikováno v:
Journal of Molecular Structure: THEOCHEM. 388:145-159
The enzyme-catalyzed enolization of acetaldehyde has been studied using ab initio methods. The energetics of concerted and stepwise proton transfer pathways are compared, with the participation of a general acidic and/or a general basic catalyst. Two
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5bfa8e1f2292963cb5bd4e5e3db33d8a
https://doi.org/10.1016/s0166-1280(96)80028-5
https://doi.org/10.1016/s0166-1280(96)80028-5