Molecular polarizability and polarizability derivatives in cyclohexane analyzed with the theory of atoms in molecules

1994 ◽  
Vol 98 (3) ◽  
pp. 771-776 ◽  
Author(s):  
Kathlene M. Gough ◽  
Hemant K. Srivastava ◽  
Katarina Belohorcova
Keyword(s):  
Atoms In Molecules ◽  
Molecular Polarizability

Analysis of molecular polarizabilities and polarizability derivatives in H2, N2, F2, CO, and HF, with the theory of atoms in molecules

1996 ◽  
Vol 74 (6) ◽  
pp. 1139-1144 ◽  
Author(s):  
Kathleen M. Gough ◽  
Margaret M. Yacowar ◽  
Richard H. Cleve ◽  
Jason R. Dwyer
Keyword(s):  
Charge Transfer ◽  
Ab Initio ◽  
Molecular Orbital ◽  
Atoms In Molecules ◽  
Molecular Polarizability ◽  
Molecular Orbital Calculations ◽  
Induced Dipole ◽  
Order Of Magnitude ◽  
Atomic Dipole ◽  
Molecular Polarizabilities

Ab initio molecular orbital calculations have been performed on the title molecules at the SCF-HF and MP2 levels to obtain molecular polarizabilities and the derivatives associated with bond stretch. The wave functions from these calculations have been analyzed with the theory of atoms in molecules (AIM). Both the polarizability and its derivative are successfully reconstructed from AIM terms representing the transfer of charge between atoms (CT = charge transfer) and the rearrangement of charge within an atomic basin (AD = atomic dipole). The results for the diatomics are compared to each other and to the alkanes studied previously. Equilibrium polarizabilities are qualitatively explained with reference to atomic electronegativity and type of bonding. While derivatives of the mean molecular polarizability differ by a factor of two at most, individual contributions vary by an order of magnitude. The derivatives along the bond axis for H2 are ΔCT = 2.06 and ΔAD = −0.62 × 10−30 C m/V, while for N2 they are ΔCT = 13.77 and ΔAD = −10.00 × 10−30 C m/V. The common feature observed is that as the induced dipole due to charge transfer increases, the induced dipole due to changes in the atomic dipole also increases and opposes it. Key words: diatomic molecules, molecular polarizability, molecular polarizability derivative, theory of atoms in molecules, ab initio molecular orbital calculations.

Ab initio analysis of C-H and C-C stretching intensities in Raman spectra of hydrocarbons

2000 ◽  
Vol 78 (7) ◽  
pp. 1035-1043 ◽  
Author(s):  
Kathleen M Gough ◽  
Jason R Dwyer ◽  
Richard Dawes
Keyword(s):  
Raman Scattering ◽  
Ab Initio ◽  
Chain Length ◽  
Raman Spectra ◽  
Atoms In Molecules ◽  
Molecular Polarizability ◽  
Saturated Hydrocarbons ◽  
Work Location ◽  
Location Type ◽  
Significant Factors

Molecular polarizability and changes in the polarizability associated with the stretch of C–C and C–H bonds have been calculated for thirty-four saturated hydrocarbons, including the series of n-alkanes to C15, as well as several cyclo- and bicycloalkanes, propellanes, prismanes, and hedranes. The ab initio results (HF/D95(d,p)) are compared to experimental Raman trace scattering intensities where such information is available. Possible factors governing trends in the magnitude of the derivatives are considered. For the C–C stretches, chain length and position along the chain are the most important factors for the n-alkanes, whereas strain appears to be significant for the ring and caged structures. For the C–H stretches, the most significant factors are the same as those found in our earlier work: location, type, and orientation relative to the carbon skeleton.Key words: hydrocarbons, Raman scattering intensities, molecular polarizability, polarizability derivatives, theory of atoms in molecules.

scholarly journals Halogen bonding. The role of the polarizability of the electron-pair donor

2016 ◽  
Vol 18 (10) ◽  
pp. 7300-7309 ◽  
Author(s):  
Darío J. R. Duarte ◽  
Gladis L. Sosa ◽  
Nélida M. Peruchena ◽  
Ibon Alkorta
Keyword(s):  
Theoretical Calculation ◽  
Electron Pair ◽  
Decomposition Analysis ◽  
Halogen Bonding ◽  
Atoms In Molecules ◽  
Molecular Polarizability ◽  
Aim Analysis ◽  
Molecular Potential

The nature of F–Br⋯X–R interactions (with X = Cl, Br, I and R = –H, –F) has been investigated through theoretical calculation of molecular potential electrostatic (MEP), molecular polarizability, atoms in molecules (AIM) analysis and energetic decomposition analysis (EDA).

Ab initio charge density analysis of (B6C)2– and B4C3 species — How to describe the bonding pattern?

2006 ◽  
Vol 84 (5) ◽  
pp. 771-781 ◽  
Author(s):  
Cina Foroutan-Nejad ◽  
Gholam Hossein Shafiee ◽  
Abdolreza Sadjadi ◽  
Shant Shahbazian
Keyword(s):  
Quantum Theory ◽  
Carbon Atom ◽  
Charge Density ◽  
Ab Initio ◽  
Atoms In Molecules ◽  
Central Carbon Atom ◽  
B3lyp Method ◽  
Central Carbon ◽  
Density Analysis ◽  
Concrete Ring

In this study, a detailed topological charge density analysis based on the quantum theory of atoms in molecules (QTAIM) developed by Bader and co-workers, has been accomplished (using the B3LYP method) on the CB62– anion and three planar isomers of the C3B4 species, which had been first proposed by Exner and Schleyer as examples of molecules containing hexacoordinate carbon atoms. The analysis uncovers the strong (covalent) interactions of boron atoms as well as the "nondirectional" interaction of central carbon atom with those peripheral atoms. On the other hand, instabilities have been found in the topological networks of (B6C)2– and B4C3(para) species. A detailed investigation of these instabilities demonstrates that the topology of charge density has a floppy nature near the equilibrium geometries of the species under study. Thus, these species seems to be best described as complexes of a relatively concrete ring containing boron or carbon atoms and a central carbon atom that is confined in the plane of the molecule, but with nondirectional interactions with the surrounding atoms.Key words: hypervalency, hexacoordinate carbon, quantum theory of atoms in molecules, charge density analysis, ab initio methods.

Sign in / Sign up

Export Citation Format

Share Document