ChemInform Abstract: MNDO Method of Studies of Isomers of C6H6

Using semiempirical MNDO method of quantum chemistry the optimal geometries and corresponding electronic structures of [Pb3(OH)n]6-n model systems as well as of their hydrated [Pb3(OH)n(H2O)8-n]6-n analogues (n = 4, 5) are investigated. The most stable trinuclear lead(II) complexes present in aqueous solutions correspond to cyclo-(μ3-OH)(μ2-OH)3Pb32+, Pb(μ-OH)2Pb(μ-OH)2Pb2+, cyclo-(μ3-OH)2(μ2-OH)3Pb3+, Pb(OH)(μ-OH)2Pb(μ-OH)Pb(OH)+ and Pb(OH)(μ-OH)2Pb(μ-OH)2Pb+ systems. The key role of OH bridges (by vanishing direct Pb-Pb bonds) on the stability of individual isomers is discussed.

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MNDO CI study of the photoisomerization of pentadieniminium

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19902874 ◽

1990 ◽

Vol 55 (12) ◽

pp. 2874-2879 ◽

Cited By ~ 2

Author(s):

Peter Ertl

Keyword(s):

Schiff Base ◽

Double Bond ◽

Configuration Interaction ◽

Mndo Method ◽

Double Bonds

Photoisomerization mechanism in model retinal-like protonated Schiff base pentadieniminium was investigated by using MNDO method with configuration interaction. Isomerizations around various double bonds were studied and twisted biradical geometries in S0 and S1 states were optimized. Photoisomerization proceeds exclusively around the central double bond where the twisted S1 state is strongly stabilized and the S0-S1 gap is minimal.

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Quantum-chemical calculations by the MNDO method of the pre-exponential factor for the homolytic decomposition of aliphatic nitro and ?-fluoronitro compounds in the gas phase

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science ◽

10.1007/bf00960653 ◽

1990 ◽

Vol 39 (2) ◽

pp. 283-286

Author(s):

K. I. Rezchikova ◽

V. N. Solkan ◽

S. L. Kuznetsov

Keyword(s):

Gas Phase ◽

Quantum Chemical Calculations ◽

Quantum Chemical ◽

Mndo Method ◽

Exponential Factor ◽

Homolytic Decomposition

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Theoretical investigation of the electronic structure of graphite + LiNH2 intercalation compounds by the MNDO method

Journal of Structural Chemistry ◽

10.1007/bf00777182 ◽

1991 ◽

Vol 32 (2) ◽

pp. 168-171 ◽

Cited By ~ 2

Author(s):

V. L. Pershin ◽

E. I. Overchuk

Keyword(s):

Electronic Structure ◽

Theoretical Investigation ◽

Mndo Method ◽

Intercalation Compounds

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MNDO method for calculations of magnesium clusters

Russian Chemical Bulletin ◽

10.1007/bf00703682 ◽

1994 ◽

Vol 43 (8) ◽

pp. 1310-1314 ◽

Cited By ~ 1

Author(s):

A. E. Liashenko ◽

V. V. Smirnov ◽

V. I. Faustov

Keyword(s):

Mndo Method

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MNDO calculations for some allotropes, hydrides, and oxides of phosphorus

Canadian Journal of Chemistry ◽

10.1139/v84-060 ◽

1984 ◽

Vol 62 (2) ◽

pp. 341-347 ◽

Cited By ~ 32

Author(s):

N. Colin Baird

Keyword(s):

Molecular Orbital ◽

Strain Energy ◽

Mndo Method ◽

Molecular Orbital Calculations ◽

Mndo Calculations

Molecular orbital calculations by the MNDO method are reported for some allotropes, hydrides, and oxides of phosphorus. The aim of the study is to test further the ability of MNDO to reproduce the energetics of PP, PH, and PO bonds, and to apply MNDO to interesting problems in the chemistry of such systems. Different isomers of P4, P6, and P8 are considered, as well as ions of P3, P5, and P7. The method is found to overestimate strain energy in three-membered rings, and to underestimate the strength of three-electron PP bonds. The strength of PO π bonds apparently also is overestimated. Possible isomers of P2O2 and P2O3 are discussed.

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On the Structure of Lead(II) Complexes in Aqueous Solutions. III. Hexanuclear Clusters

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20020219 ◽

2002 ◽

Vol 67 (2) ◽

pp. 219-227 ◽

Cited By ~ 9

Author(s):

Martin Breza ◽

Alena Manová

Keyword(s):

Quantum Chemistry ◽

Aqueous Solutions ◽

Electronic Structures ◽

Mndo Method ◽

Experimental Techniques ◽

Hexanuclear Clusters ◽

Semiempirical Mndo

Optimum geometries based on experimental structures and corresponding electronic structures of [Pb6(μ3-OH)8]4+ and [Pb6O(μ3-OH)6]4+ clusters as well as of their hydrated [Pb6(μ3-OH)8(H2O)6]4+ and [Pb6O(μ3-OH)6(H2O)6]4+ analogues are investigated using the semiempirical MNDO method of quantum chemistry. Direct Pb-Pb and O-O bonds are vanishing in the systems under study. Small differences in interatomic Pb-Pb and Pb-O distances between these clusters indicate that they cannot be distinguished by recent experimental techniques in solution. Both the mentioned structures are stable and might coexist in solution.

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