The photochemistry of stilbene: some s. c. f. molecular orbital calculations

1967 ◽  
Vol 298 (1455) ◽  
pp. 453-466 ◽  
Keyword(s):  
Double Bond ◽  
Potential Energy ◽  
Molecular Orbital ◽  
Excited States ◽  
Ground State ◽  
Electron Distribution ◽  
Stable State ◽  
Quantitative Agreement ◽  
Molecular Orbital Calculations ◽  
Fluorescent Spectra

Potential energy diagrams for ground and excited states have been calculated approximately for trans stilbene and several geometrical configurations, including a planar cis form, generated by twisting about the central double bond. The calculations show that on twisting the lowest triplet 3 B becomes the most stable state, and that the π -electron distribution of this state in the perpendicular model is equivalent to separation into two benzyl systems. The lowest singlet 1 A that corresponds to the ground state in cis and trans stilbene does not separate in this way. Quantitative agreement is obtained with observed thermal and spectroscopic evidence. The potential energy diagrams provide a satisfactory interpretation of the qualitative features of the ultraviolet and fluorescent spectra, the absence of phosphorescence, and the mechanisms of the thermal, the photochemical and the photosensitized isomerization reactions.

Molecular Orbital Calculations on Penta Coordinated Ferric Dithiocarbamates Exhibiting Intermediate and Low Spin Ground States

1979 ◽  
Vol 34 (12) ◽  
pp. 1500-1506
Author(s):  
P. Ganguli ◽  
K. M. Hasselbach
Keyword(s):  
Energy Level ◽  
Molecular Orbital ◽  
Ground State ◽  
Ground States ◽  
Orbital Energy ◽  
Iron Nucleus ◽  
Molecular Orbital Calculations ◽  
Valence Shell ◽  
Molecular Orbital Energy ◽  
Orbital Energy Level

Abstract SCCEHMO calculations show that the ground state in [Fe(dtc)2X], X = Cl, Br, I and NCS, is 4A2: (x2 - y2)2(xz)1(yz)1(z2)1(xy)0 and for X = NO is 2A1: (xz)2(yz)2(x2-y2)2(z2)1(xy)0. The calculated quadrupole splittings of iron and iodine included the valence shell, overlap charge, and the ligand and lattice contributions to the EFG tensor at the nuclei. In addition, the elec-tron densities at the iron nucleus are compared with the measured isomer shifts. The spin densi-ties may be interpreted in terms of a π-delocalization. The results are discussed on the basis of the molecular orbital energy level schemes.

Molecular Orbital Calculations of Excited States of H2

1962 ◽  
Vol 36 (8) ◽  
pp. 2140-2144 ◽  
Author(s):  
Joseph T. Zung ◽  
A. B. F. Duncan
Keyword(s):  
Molecular Orbital ◽  
Excited States ◽  
Molecular Orbital Calculations

Ab initio molecular orbital calculations of the ground and excited states of the permanganate and chromate ions

1970 ◽  
Vol 320 (1541) ◽  
pp. 161-173 ◽  
Keyword(s):  
Molecular Orbital ◽  
Excited States ◽  
Slater Type Orbitals ◽  
Molecular Orbital Calculations ◽  
Field Equations ◽  
Chromate Ions ◽  
Consistent Field ◽  
Self Consistent ◽  
Self Consistent Field ◽  
State Wavefunctions

The bonding in the permanganate and chromate ions is described by means of self-consistent field molecular orbital calculations employing a basis of Slater type orbitals expanded in Gaussian type functions. A new procedure for the solution of the self-consistent field equations is described and applied to the ions studied here. Excited state wavefunctions are calculated using configuration interaction considering all singly excited configurations involving all virtual and valence orbitals. The calculated transition energies and transition moments are compared with those from the experimental electronic spectra.

scholarly journals Spectrum of scalar and pseudoscalar glueballs from functional methods

2020 ◽  
Vol 80 (11) ◽  
Author(s):  
Markus Q. Huber ◽  
Christian S. Fischer ◽  
Hèlios Sanchis-Alepuz
Keyword(s):  
Excited States ◽  
Ground State ◽  
Quantitative Agreement ◽  
Ghost Propagator ◽  
Yang Mills ◽  
Functional Methods ◽  
Specific Choice ◽  
The Masses ◽  
Self Consistency

AbstractWe provide results for the spectrum of scalar and pseudoscalar glueballs in pure Yang–Mills theory using a parameter-free fully self-contained truncation of Dyson–Schwinger and Bethe–Salpeter equations. The only input, the scale, is fixed by comparison with lattice calculations. We obtain ground state masses of $$1.9\,\text {GeV}$$ 1.9 GeV and $$2.6\,\text {GeV}$$ 2.6 GeV for the scalar and pseudoscalar glueballs, respectively, and $$2.6\,\text {GeV}$$ 2.6 GeV and $$3.9\,\text {GeV}$$ 3.9 GeV for the corresponding first excited states. This is in very good quantitative agreement with available lattice results. Furthermore, we predict masses for the second excited states at $$3.7\,\text {GeV}$$ 3.7 GeV and $$4.3\,\text {GeV}$$ 4.3 GeV . The quality of the results hinges crucially on the self-consistency of the employed input. The masses are independent of a specific choice for the infrared behavior of the ghost propagator providing further evidence that this only reflects a nonperturbative gauge completion.

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