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

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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Molecular orbital calculations for dialuminum and disilicon hydrides and related systems

Canadian Journal of Chemistry ◽

10.1139/v85-013 ◽

1985 ◽

Vol 63 (1) ◽

pp. 71-76 ◽

Cited By ~ 18

Author(s):

N. Colin Baird

Keyword(s):

Molecular Orbital ◽

Electron Correlation ◽

Surface Structures ◽

Molecular Orbital Calculations ◽

Mo Calculations ◽

Mndo Calculations ◽

Derivatives Of

Abinitio MO calculations for Si2H2 are reviewed and discussed in qualitative terms. New calculations are reported, by MNDO for Si2H2 and Si2H4, and using both MNDO and abinitio methods (including electron correlation at the MP2 level) for various possible structures for Al2H2 (3). As with the analogous silicon dihydride, a dibridged structure 3a is found to be superior to classical structures 3b, 3c, and 3d. MNDO calculations for derivatives of Al2H2 are reported. Finally, some implications of the calculations for the surface structures of partially-hydrogenated elemental aluminum and silicon are discussed.

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Interactions between Methylene Blue and Pullulan According to Molecular Orbital Calculations

IEEJ Transactions on Fundamentals and Materials ◽

10.1541/ieejfms.140.529 ◽

2020 ◽

Vol 140 (11) ◽

pp. 529-533

Author(s):

Pasika Temeepresertkij ◽

Saranya Yenchit ◽

Michio Iwaoka ◽

Satoru Iwamori

Keyword(s):

Methylene Blue ◽

Molecular Orbital ◽

Molecular Orbital Calculations

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Electronic Properties for Medicine Inhibiting Cancer Metastasis (2) : Molecular Mechanics and Molecular Orbital Calculations for Urokinase

Journal of Computer Aided Chemistry ◽

10.2751/jcac.5.70 ◽

2004 ◽

Vol 5 ◽

pp. 70-78 ◽

Cited By ~ 3

Author(s):

Naoya Tsumura ◽

Fumitaka Sugiura ◽

Hiroshi Kobayashi ◽

Noriyuki Kurita

Keyword(s):

Electronic Properties ◽

Molecular Mechanics ◽

Molecular Orbital ◽

Cancer Metastasis ◽

Molecular Orbital Calculations

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Atomic and electronic structures of boron nitride nanohorns studied by high-resolution electron microscopy and molecular orbital calculations

Diamond and Related Materials ◽

10.1016/j.diamond.2004.12.050 ◽

2005 ◽

Vol 14 (3-7) ◽

pp. 1183-1189 ◽

Cited By ~ 11

Author(s):

Atsushi Nishiwaki ◽

Takeo Oku

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Boron Nitride ◽

Molecular Orbital ◽

Electronic Structures ◽

High Resolution Electron Microscopy ◽

Molecular Orbital Calculations ◽

Resolution Electron

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Proposal of novel natural inhibitors of severe acute respiratory syndrome coronavirus 2 main protease: Molecular docking and ab initio fragment molecular orbital calculations

Biophysical Chemistry ◽

10.1016/j.bpc.2021.106608 ◽

2021 ◽

Vol 275 ◽

pp. 106608

Author(s):

Divya Shaji ◽

Shohei Yamamoto ◽

Ryosuke Saito ◽

Ryo Suzuki ◽

Shunya Nakamura ◽

...

Keyword(s):

Molecular Docking ◽

Severe Acute Respiratory Syndrome ◽

Ab Initio ◽

Molecular Orbital ◽

Molecular Orbital Calculations ◽

Fragment Molecular Orbital ◽

Main Protease ◽

Natural Inhibitors

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A pairwise additivity scheme for conformational energies of substituted ethanes

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1975.0048 ◽

1975 ◽

Vol 343 (1632) ◽

pp. 1-10 ◽

Cited By ~ 9

Keyword(s):

Large Deviations ◽

Ab Initio ◽

Dihedral Angle ◽

Molecular Orbital ◽

Methyl Groups ◽

Molecular Orbital Calculations ◽

Linear Combinations ◽

Strongly Interacting ◽

Conformational Energies

Ab initio molecular orbital calculations are used to explore additivity in the conformational energies of poly-substituted ethanes in terms of conformational energies of ethane and appropriate mono- and 1,2-di-substituted derivatives. Such relations would allow complex calculations for poly-substituted ethanes to be replaced by much simpler ones on a small number of parent molecules. General expressions for the linear combinations are derived from the assumption that interactions between vicinal substituents are pairwise additive and depend only on the vicinal dihedral angle. The additivity scheme is tested for 15 ethanes, di-, tri- or tetrasubstituted by cyano and methyl groups and for a smaller number of fluoroethanes. Additivity applies to within 0.1- 0.3 k J mol -1 in the methylethanes and mostly to within about 0.7- 0.8 kJ mol -1 in cyanoethanes. Large deviations are found among the geminally substituted fluoroethanes. It is suggested that the additivity approximation is most successful in the absence of strongly interacting geminal groups. Predictions are made of conformational energies of ten hexa(cyano- and methyl-) substituted ethanes.

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