Models in Quantum Chemistry  Page description

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Details of project

 
Identifier
49718
Type K
Principal investigator Surján, Péter
Title in Hungarian Modellek a kvantumkémiában
Title in English Models in Quantum Chemistry
Panel Chemistry 1
Department or equivalent Institute of Chemistry (Eötvös Loránd University)
Participants Kállay, Mihály
Kohalmi, Dóra
Rolik, Zoltán
Szabados, Ágnes
Tóth, Gábor
Zólyomi, Viktor
Starting date 2005-01-01
Closing date 2009-12-31
Funding (in million HUF) 13.600
FTE (full time equivalent) 13.93
state closed project





 

Final report

 
Results in Hungarian
Lineárisan skálázódó módszert fejlesztettünk ki abból a célból, hogy elkerüljük az egyelektron Hamilton-mátrixok diagonalizálását, amely köbösen skálázódó procedúra. A multikonfigurációs perturbációszámítás több változátát dolgoztuk ki, teszteltük, és hasonlítottuk össze más perturbációs sémákkal. Bevezettük a hiper-hartree-Fock módszert, ami magasabb rangú (több, mint kételektron-kölcsönhatást tartalmazó) operátorok speciális átlagolási szisztémája. A full-CI probléma skálázódási tulajdonságait ritka-mátrixos technikák alkalmazásával javítottuk. A lokális kémiai kölcsönhatások leírása céljából javasoltuk az ún. FLMO (Frozen Localized Molecular Orbitals) eljárást, amely a Hartree-Fock megoldást a molekulapályák explicit megkonstruálása nélkül szolgáltatja az egész nagy molekulára a sűrűségmátrixon keresztül, a korralációt azonban csak az aktív molekularészletre szám1tja ki. Kimutattuk, hogy a korrelációs energia explicit funkcionálja a Hartree-Fock sűrűségmátrixnak, és a levezettük másodrendű energiaképlet funkcionálját. A kutatás során 21 tudományos közleményt publikáltunk nemzetközi folyóiratokban.
Results in English
A linear-scaling algorithm was developed for avoiding the diagonalization of large one-electron Hamiltonian matrices, which is a cubicly scaling procedure. Several versions of the multi-configuration perturbation theory was developed, tested, and compared to other methods. The so-called hyper Hartree-Fock methods was introduced, which is a special averaging scheme for high-rank Hamiltonians, i.e., those describing higher than two-particle interactions. To describe local interactions in chemical systems, the FLMO (Frozen Localized Molecular Orbitals) model was developed, which avoids constructing molecular orbitals but solves the Hartree-Fock problem via the density matrix, then computes electron correlation for the active site only. It was proven that the correlation energy is an explicit functional of the Hartree-Fock density matrix, and this functional was constructed at the second order. Te project resulted 21 publications in international journals.
Full text https://www.otka-palyazat.hu/download.php?type=zarobeszamolo&projektid=49718
Decision
Yes





 

List of publications

 
R K. Chaudhuri, K F. Freed, G Hose, P Piecuch, K Kowalski, M Wloch, S Chattopadhyay, D Mukherjee, Z Rolik, A Szabados, G Toth, and P R. Surjan: Comparison of low-order multireference many-body perturbation theories, J.Chem.Phys. 122 134105, 2005
Lijie Wang, Peter L. Warburton, Zsolt Szekeres, Peter Surjan and Paul G. Mezey: Stability and Properties of Polyhelicenes and Annelated Fused-Ring Carbon Helices: Models Toward Helical Graphites, J. Chem. Inf. Model. 45 850--855, 2005
Zs. Szekeres, P.G. Mezey and P. R. Surjan: Diagonalization-free initial guess to SCF calculations for large molecules, Chem.Phys.Letters 424 420-424 (2006), 2006
P. R. Surjan and G. Toth: The High-rank Hartree-Fock Method as an Averaging Procedure, Molecular Physics 104 2037--2046, 2006
Z. Rolik, A. Szabados, D. K\H ohalmi P. R. Surjan: Coupled-cluster theory and the method of moments, J.Mol.Struct. {\sc THEOCHEM} {\bf 768} 17--23, 2006
V. Z\'olyomi, 1, Á. Ruszny\'ak, J. K\''urti, \'A. Gali, F. Simon, H. Kuzmany, \'A. Szabados, and P. R. Surj\'an: Semiconductor-to-metal transition of double walled carbon nanotubes induced by inter-shell interaction, phys. stat. sol. (b), 1–4 (2006) / DOI 10.1002/pssb.200669161, 2006
Peter Szakacs and Peter S. Surjan: Stability conditions for the Coupled Cluster Equations, Int. J. Quantum. Chem. 108 2043--2052 (2008), 2008
J. Noga M. Kallay and P. Valiron: On the role of high excitations in the intermolecular potential of H2CO, Mol. Phys. 13–14, 10–20 July 2006, 2337–2345, 2006
Kürti Jenő, Kamarás Katalin, Szalay Péter és Surj\'an P\'eter: Teller Ede ujjlenyomatai a molekulafizikában (Teller Ede 100-adik születésnapjára), Magyar Tudomány {\bf III.} 301, 2008
P\'eter Szak\'acs and P\'eter R. Surj\'an: Iterative solution of Bloch-type equations: stability conditions and chaotic behavior, J. Math. Chem. 43 314, 2008
T. A. Rokob, \'A. Szabados and P. R. Surj\'an: A note on the symmetry properties of L\"owdin's orthogonalization, Coll. Czech.Chem.Commun. 73 937--944 (2008), 2008
Z. Rolik and A. Szabados: Multipartitioning Moller-Plesset perturbation theory: size-extensivity at third order and symmetry conservation, Int. J. Quantum. Chem. (accepted for publication), 2009
D. K\H ohalmi, A. Szabados and P. R. Surj\'an: Idempotency-conserving iteration scheme for the one-electron density matrix, Phys. Rev. Letters 95 13002, 2005
P. R. Surj\'an: The MP2 energy as a functional of the Hartree-Fock density matrix, Chem.Phys.Letters 406 318--320, 2005
A. Szabados, L. P. Biro and P. R. Surjan: Inter-tube interaction in carbon nanotube bundles, Phys. Rev. B 73 195404, 2006
Ágnes Szabados: Theoretical interpretation of Grimme’s spin-component-scaled second order Møller-Plesset theory, JOURNAL OF CHEMICAL PHYSICS 125, 214105, 2006
P\'eter R. Surj\'an: Natural orbitals in CIS and singular-value decomposition, Chem.Phys.Letters 439 393–394, 2007
P\'eter R. Surj\'an, D\'ora K\H ohalmi, Zolt\'an Rolik and \'Agnes Szabados: Frozen Localized Molecular Orbitals in Electron Correlation Calculations -- Exploiting the Hartree-Fock Density Matrix, Chem. Phys. Letters 450 400--403, 2007
P\'eter Szak\'acs, Debashis Mukherjee, Sanghamitra Das: Effective \pii-electron Hamiltonian for small-radii nanotubes: novel interpretation of curvature-induced conductivity of the (5,0) carbon nanotube, Phys. Rev. B (Brief Commun.) B 77, 193407 (2008), 2008
Zolt\' an Rolik, \'Agnes Szabados and P\' eter R. Surj\'an: A sparse matrix based Full-CI algorithm, J. Chem.Phys. 128 144101, 2008
Zs\'ofia Szalay and P\'eter R. Surj\'an: Distorted $s$-type orbitals: the H$_2^+$ problem revisited, J. Math. Chem. 43 227, 2008
V. Z\'olyomi, J. Koltai, Á. Rusznyák, J. Kürti, Á. Gali, F. Simon, H. Kuzmany, Á. Szabados, and P. R. Surján: Intershell interaction in double walled carbon nanotubes: Charge transfer and orbital mixing, Phys. Rev. B 77 245403, 2008




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