The Electronic Ground State

Conjngated polymers differ from crystalline semiconductors and metals in several aspects and are often treated theoretically as a one-dimensional system. The formation of the band gap is explained taking into account either electron-phonon interactions or electron-electron interactions among 7t-electrons. If electron-phonon interaction dominates in real 7t-conjugated polymers, these systems could be treated using Peierls theory. In contrast, when electron-electron interactions dominate, the Hubbard model could be used to explain the physical properties of polymers. 

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State I ) m the electronic ground state. In principle, other possibilities may also be conceived for the preparation step, as discussed in section A3.13.1, section A3.13.2 and section A3.13.3. In order to detemiine superposition coefficients within a realistic experimental set-up using irradiation, the following questions need to be answered (1) Wliat are the eigenstates (2) What are the electric dipole transition matrix elements (3) What is the orientation of the molecule with respect to the laboratory fixed (Imearly or circularly) polarized electric field vector of the radiation The first question requires knowledge of the potential energy surface, or... 

Barker J R 1984 Direct measurement of energy transfer in rotating large molecules in the electronic ground state J. Chem. Phys. 88 11... 

A) During the luultiphoton excitation of molecular vibrations witli IR lasers, many (typically 10-50) photons are absorbed in a quasi-resonant stepwise process until the absorbed energy is suflFicient to initiate a unimolecular reaction, dissociation, or isomerization, usually in the electronic ground state. 

Kuhn B, Rizzo T R, Luckhaus D, Quack M and Suhm M A 1999 A new six-dimensional analytical potential up to chemically significant energies for the electronic ground state of hydrogen peroxide J. Chem. Phys. Ill 2565-87... 

Oppenlieimer potential which is defined as the electronic ground-state energy for nuclear configuration T, including the niiclear-niiclear repulsion. 

Hence, in order to contract extended BO approximated equations for an N-state coupled BO system that takes into account the non-adiabatic coupling terms, we have to solve N uncoupled differential equations, all related to the electronic ground state but with different eigenvalues of the non-adiabatic coupling matrix. These uncoupled equations can yield meaningful physical... 

The best solution to date for the electronic ground state is that of Wind (1965) who found an electronic energy (relative to infinitely separated nuclei and electrons) of —0.602634 2 h, which corresponds to a dissociation energy... 

Table 3.2 records historically significant calculations for the electronic ground state of H2+. 

We can construct a total electronic wavefunction as the product of a spatial part and a spin part. For the electronic ground state of H2 we can consider combinations of the two spatial terms... 

In Chapter 3, I showed you how to write a simple LCAO wavefunction for the electronic ground state of the hydrogen molecule-ion, H2 ... 

It turns out that /Sec is a negative quantity, so the electronic ground state of ethene corresponds to orbital configuration where... 

In the electronic ground state, the six rr-electrons occupy the three lowest-energy orbitals (the first three from Table 7.2). The Huckel rr-electron charge density matrix is... 

In HF-LCAO theory, the electronic ground state of pyridine is We... 

We would normally write the electronic ground state electron configuration of a carbon atom as ls-2s 2p-. Despite the intellectual activity that has gone into defining mythical valence states for carbon atoms in different bonding situations, no one would include a d-orbital in the description of ground state carbon. 

Consider the electronic ground state of dicarbon C2. Elementary arguments would suggest a ground state configuration... 

Regarding AS, the simplest assumption we can make is that it comes entirely from the loss of translational and rotational degrees of freedom of the oxygen molecule when it is absorbed into the crystal. A standard calculation then gives (the electronic ground state of O2 is a triplet)... 

Although magnetic properties of a number of plutonium compounds are known, it seems from the above discussion that the knowledge of the electronic ground state properties is very limited. Each compound represents a system of its own which has to be... 

Such an averaging effect of the transition energies of CrMo relative to Crj and Mo is intuitively understandable, as the electronic ground-states of Cr and Mo atoms are both nsHn — l)d and those of Cr and M02 are both considered to be lo-gj 17Tu4 2a-g 18,4. Furthermore, the Cr 4s, 3d and the Mo 5s, 4d atomic orbitals, considered to be the main contributors to the metal-metal bonding in Cr /CrMo/Mo, lu-e known to have similar energies. Further discussion of these bimetallics formed by cryophotoclustering methods will be found in Section III. 

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