Introducing DDEC6 atomic population analysis: part 4. Efficient parallel computation of net atomic charges, atomic spin moments, bond orders, and more

Abstract Isocyanide-nitrile rearrangement has long been a continuing and interesting topic. A series of nitriles and isocyanides with the substituents of R=-AlH2, -BeH, -BH2, -C ≡ CH, -CF3, -CH3, -Cl, -C ≡ N, -COOH, -F, -H, Li, -MgH, -Na, -NH2, -NO2, -OH, -PH2, -SH, -SiH3, -CH = CH2 were investigated systematically based on full optimization at B3LYP-D3(BJ)/def2-QZVP level, and the isomerization energies from R-C ≡ N to :C = N-R were estimated. The substituent effect and bonding characters were analyzed by surface ESP colored van der Waals surfaces in conjunction with the global and local electrostatic extrema, the population analyses in terms of Hirshfeld and ADCH atomic charges, and bond order analyses via Laplacian and fuzzy bond orders.

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ChemInform Abstract: Ab Initio Study of Hydrogen, Lithium and Sodium Bonding on the Basis of Atomic Charges, Valencies, Bond Orders and Overlap Populations

ChemInform ◽

10.1002/chin.198821004 ◽

1988 ◽

Vol 19 (21) ◽

Author(s):

T. KAR ◽

A. B. SANNIGRAHI ◽

B. G. NIYOGI

Keyword(s):

Ab Initio ◽

Atomic Charges ◽

Bond Orders ◽

Ab Initio Study

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Comparison of atomic charges, valencies and bond orders in some hydrogen-bonded complexes calculated from Mulliken and Löwdin SCF density matrices

Journal of Molecular Structure THEOCHEM ◽

10.1016/0166-1280(87)85007-8 ◽

1987 ◽

Vol 153 (1-2) ◽

pp. 93-101 ◽

Cited By ~ 23

Author(s):

Tapas Kar ◽

A.B. Sannigrahi ◽

D.C. Mukherjee

Keyword(s):

Atomic Charges ◽

Bond Orders ◽

Density Matrices ◽

Bonded Complexes ◽

Hydrogen Bonded

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Kritische Betrachtungen zu Ladungsverteilungen in Molekülen, erhalten durch SCF-MO-LCAO- Rechnungen

Zeitschrift für Naturforschung A ◽

10.1515/zna-1970-0233 ◽

1970 ◽

Vol 25 (2) ◽

pp. 311-312

Author(s):

R. Janoschek

Keyword(s):

Charge Distribution ◽

Population Analysis ◽

Atomic Charges ◽

Electron Charge ◽

Numerical Accuracy ◽

Electron Charge Distribution

Abstract The numerical accuracy of population analysis as a tool for discussing the electron charge distribution in molecules is discussed. Theoretical bounds for the gross atomic charges resulting from the SCF-MO-LCAO method are derived. Calculated gross atomic charges which do not conform to these bounds are therefore inexact.

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Epitaxial Layers of FCC FE on CU(001)

MRS Proceedings ◽

10.1557/proc-143-298 ◽

1988 ◽

Vol 143 ◽

Author(s):

R. F. Willis ◽

R. Morra ◽

F. d'Almeida ◽

G. Mankey ◽

M. Kief

Keyword(s):

Magnetic Anisotropy ◽

Density Functional ◽

Structural Investigation ◽

Layer By Layer ◽

Magnetic Exchange ◽

Lattice Volume ◽

Atomic Spin ◽

Magnetic Exchange Coupling ◽

Spin Moments ◽

Reflectance Measurements

Metastable films of fcc Fe epitaxed to Cu(001) show unusual ferromagnetic properties(1). Changes in the lattice volume occur with film thickness in the 1 to 5 monolayer range, reflecting changes in the magnitude of the spin moments and the magnetic exchange coupling. The associated uniaxial strain is manifest in strong magnetic anisotropy, layer by layer lattice expansion, phonon softening, and surface layer atomic reconstructions. We present LEED results of a detailed structural investigation, neutron reflectance measurements of the spin moments, surface magneto-optic Kerr effect studies of the magnetic anisotropy, and angle resolved photoemission of the electronic states. The observed effects are due to the strain-related kinetic energy associated with the formation of the atomic spin moments, predicted by spin-density-functional calculations of bulk fcc Fe(2).

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