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All-electron ab initio Hartree-Fock (HF), multiconfiguration self-consistent-field (CASSCF), and configuration interaction (Cl) calculations have been carried out to determine the low-lying electronic states of the Ga2 molecule. Six states, bound relative to the 2P ground-term Ga atoms, have been identified in the Cl calculations. The Ga2 molecule has a 3 " electronic ground state, and the next higher lying states are 32¡, l'2g, 'II", * ,, and 2'2g. The calculated vibrational frequency for the 3 " ground state, 175 cm , compares well with the experimental value of 180 cm"1 11. The six lowest lying electronic states have been rationalized in a simple molecular orbital diagram. On the basis of wave functions determined in valence Cl calculations, the oscillator strengths have been computed for selected dipole-allowed transitions. Our calculated transition energies and oscillator strengths compare favorably with the available absorption and emission spectra of Ga2. An approximate treatment of the spin-orbit coupling in the low-lying electronic states of the Ga2 molecule has been carried out. The four lowest lying spin-orbit coupled states, 0¡¡, 0*, lu, 2^, are essentially the split 3 " state. The next higher lying state, 0Í, exhibits a double minimum due to the mixing of the states 32¡ and ' ,. The dissociation energy of the Ga2 molecule has been determined from the high-temperature mass spectrometric data combined with the experimental vibrational frequency and the spin-orbit coupled electronic states from the present work as D'0 = 110.3 ± 7 kJ mol"1.

All-electron ab initio Hartree-Fock (RHF) calculations have been carried out to investigate the ketoienol equilibrium of phloroglucinol. The calculations predict that the enol form of phloroglucinol, 1,3,5-benzenetriol, is by far the most stable of the two. This is confirmed by NMR spectra taken on phloroglucinol.A comparison of the keto enol form transformation of phloroglucinol with that of the phenol system shows that the keto form of phloroglucinol, 1,3,5-cyclohexanetrion, is more abundant in the phloroglucinol system, and the keto form of phenol, 2,4-cyclohexadien-l-on, in the phenol system.

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