The ionization energies of some phenothiazine tranquillizers and molecules of similar structure

1968 ◽  
Vol 21 (4) ◽  
pp. 873 ◽  
Author(s):  
A Fulton ◽  
LE Lyons
Keyword(s):  
Charge Transfer ◽  
Complex Formation ◽  
Molecular Orbital ◽  
Equilibrium Constants ◽  
Electron Donors ◽  
Molecular Orbital Calculations ◽  
Strong Electron ◽  
Ionization Energies ◽  
Physiological Action ◽  
The Difference

Charge-transfer spectroscopy was used to determine the ionization energies of ten phenothiazine tranquillizers and similar molecules which are stimulants, in order to throw light on the proposed relation between physiological action and electron-donating power, and to compare the ionization energies of the phenothiazines with molecular orbital calculations. All the ionization energies obtained lie in the range 7.0-8.4 eV. The phenothiazines are thus strong electron donors, in agreement with calculations. There is little difference in ionization energies and equilibrium constants of complex formation between tranquillizers and either non-tranquillizers or stimulants. The difference in physiological action of the drugs therefore cannot be dependent on electron-donating power alone.

Molecular orbital structures of sulfones

1982 ◽  
Vol 60 (6) ◽  
pp. 730-734 ◽  
Author(s):  
Russell J. Boyd ◽  
Jeffrey P. Szabo
Keyword(s):  
Crystal Structure ◽  
Gas Phase ◽  
Molecular Orbital ◽  
Geometry Optimization ◽  
Membered Ring ◽  
Molecular Orbital Calculations ◽  
Bond Lengths ◽  
Comparison With Experiment ◽  
The Difference

Abinitio molecular orbital calculations are reported for several cyclic and acyclic sulfones. The geometries of XSO2Y, where X, Y = H, F, or CH3 are optimized at the STO-3G* level. Similar calculations are reported for the smallest cyclic sulfone, thiirane-1,1 -dioxide, as well as the corresponding sulfoxide, thiirane-1-oxide, and the parent sulfide, thiirane. Where comparison with experiment is possible, the agreement is satisfactory. In order to consider the possibility of substantial differences between axial and equatorial S—O bonds in the gas phase, as observed in the crystal structure of 5H,8H-dibenzo[d,f][1,2]-dithiocin-1,1-dioxide, STO-3G* calculations are reported for a six-membered ring, thiane-1,1-dioxide, and a model eight-membered ring. Limited geometry optimization of the axial and equatorial S—O bonds in the chair conformations of the six- and eight-membered rings leads to bond lengths of 1.46 Å with the difference being less than 0.01 Å.

Charge Transfer Interactions in the Generation of Singlet Oxygen O2(1Δg) by Strong Electron Donors

1999 ◽  
Vol 103 (15) ◽  
pp. 2705-2711 ◽  
Author(s):  
Alexander P. Darmanyan ◽  
Woojae Lee ◽  
William S. Jenks
Keyword(s):  
Charge Transfer ◽  
Singlet Oxygen ◽  
Electron Donors ◽  
Strong Electron

Ab initio Molecular Orbital Calculations of Reduced Partition Function Ratios of Polyboric Acids and Polyborate Anions

2000 ◽  
Vol 55 (6-7) ◽  
pp. 623-628 ◽  
Author(s):  
Takao Oi
Keyword(s):  
Partition Function ◽  
Ab Initio ◽  
Molecular Orbital ◽  
Equilibrium Constants ◽  
Boron Isotope ◽  
Molecular Orbital Calculations ◽  
Exact Evaluation ◽  
Reac Tions

Abstract Molecular orbital calculations at the HF/6-3 lG(d) level were carried out for polyboric acids and poly-borate anions up to a pentamer to estimate their 11B -to-10B isotopic reduced partition function ratios (RPFRs) and examine the additivity of logarithms of RPFRs. Approximate RPFR-values calculated by the use of the additivity agreed with exact RPFR-values within a margin of 1% error. This error was equivalent to a 5% error on ln(RPFR). The equilibrium constants of mono boron isotope exhange reac-tions between three-coordinate boron and four-coordinate boron ranged from 1.0203 to 1.0360 at 25 °C, indicating the importance of exact evaluation of RPFRs of polymers.

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.

The electronic absorption spectra of some N-sulfinylanilines. A molecular orbital treatment

1997 ◽  
Vol 75 (7) ◽  
pp. 934-941 ◽  
Author(s):  
R. Abu-Eittah ◽  
H. Moustafa ◽  
A.M. Al-Omar
Keyword(s):  
Absorption Spectra ◽  
Molecular Orbital ◽  
Electron Acceptor ◽  
Electronic Absorption ◽  
Electronic Absorption Spectra ◽  
Basis Sets ◽  
Theoretical Treatment ◽  
Molecular Orbital Calculations ◽  
Strong Electron ◽  
Anti Conformer

The electronic absorption spectra of N-sulfinylaniline and some of its derivatives were investigated using different solvents. The spectral behavior of the molecules indicated their planarity and that the NSO group is a strong electron acceptor. All the observed bands correspond to delocalized π → π* transitions; n → π* transition were not observed as discrete bands. Ab initio molecular orbital calculations were performed using four different basis sets. The results showed that the NSO group is nonlinear, the molecules studied are planar, and the syn conformer is more stable than the anti conformer. Keywords: N-sulfinylanilines, spectra and theoretical treatment.

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