On the basis of the density-functional theory, the properties of the reaction product [Fe(H 2 O) 5 (NO)] 2+ of the classical "brown-ring" reaction are studied via the B3LYP hybrid method. Here we have found that the Fe-N-O bond in the optimized structure of [Fe(H 2 O) 5 (NO)] 2+ is linear. In addition, the vibrational frequency, atomic net charges, and spin density are analyzed and then the solvent effects are incorporated via the polarized continuum model self-consistent reaction field. Furthermore, the excitation energies are evaluated using the CIS method. Results when compared with experimental data indicate that the spin-quartet ground state of [Fe(H 2 O) 5 (NO)] 2+ is best described by the presence of Fe II (S ) 2) antiferromagnetically coupled to NO (S ) 1 / 2 ), yielding [Fe II (H 2 O) 5 (NO)] 2+ . This is clearly different from either [Fe III (H 2 O) 5 (NO -)] 2+ or conventional textbook [Fe I (H 2 O) 5 (NO + )] 2+ assignment.

To investigate the temporary anion states of uracil, density functional theory with asymptotically corrected potentials is adopted. The stabilized Koopmans' theorem and stabilized Koopmans-based approximation are used in conjunction with an analytic continuation procedure to calculate its resonance energies and lifetimes. Results indicate the presence of several low-lying π* and σ* temporary anion states of uracil. The characteristics of these resonance orbitals are also analyzed. By comparing them with the experimental values and theoretical calculations, it is believed that the stabilization approach can provide more information on the resonance states.

The studies of shape and core-excited resonances are essential in the bonding and electronic processes of quinones. So far, the experimental results of temporary anion states for p-benzoquinone cannot be fully ascertained computationally. In this paper, both resonances of p-benzoquinone are investigated via the stabilization method (SM). For shape resonances, the stabilized Koopmans theorem is adopted in the framework of long range corrected density functional theory (LC-DFT). As for core-excited resonances, the SM coupled with long range corrected time-dependent density functional theory (LC-TDDFT) is employed. The resonance energies and lifetimes are then estimated via an analytic continuation procedure in conjunction with the stabilization plots. Using this novel combination, previous experimental results of temporary anion states can be successfully identified. It is believed that this novel approach can be an accurate and efficient methodology in the study of temporary anion states of quinones.

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The aim of this study was to investigate if there were any effects on the electroencephalogram (EEG) of human brain by the manual stimulation of Neiguan (PC 6) acupuncture site. In this paper, two groups of six healthy male volunteers of ages 27.6 ± 14.2 (mean ± SD) and 28.5 ± 13.0 (mean ± SD) and no neurological disease participated in this study. A digital storage of 12-channel EEG recorder was used and spectral analyses of the data set of 18 trials were obtained before, during, and after sham/ manual acupuncture. To minimize artefacts, all data were collected with the subjects alert but eyes closed. No significant changes (P > 0.05) were obtained for the sham acupuncture group. As for the manual acupuncture group, the needle was inserted perpendicularly into the PC 6 acupuncture site and manually stimulated about 15 to 30 seconds to achieve De Qi sensation. Needles were left in place for 30 min and then removed. Analysis of the EEG data due to acupuncture was compared to the baseline data and changes were obtained. First, all trials had an increase in the amplitude and power of the alpha band during manual acupuncture (P < 0.05) when compared with the baseline data. Secondly, in the mean time, the frequency peaks in alpha band of 12-channels were all synchronized with much smaller standard deviation (P < 0.01). Thirdly, the manual acupuncture effects of higher power and synchronized frequencies persisted for at least 10 minutes after the experiment (P < 0.05) and did not disappear immediately for all 18 experiments. Finally, we hypothesized that the higher power and synchronized rhythms in brain oscillations may have to do with autonomic nervous system.

The exponent stabilized Koopmans' theorem is used to calculate the energies of the π* anion states of 1,4,5,8-tetrahydronaphthalene. The results indicate that the ordering of π* anion states is 2 2 B 3g < 2 2 A u < 3 2 B 3g . This order of anion states is the same as that which would prevail were only through-space (TS) interactions present. The through-bond (TB) interactions destabilize all the π* orbitals; however, they do not change the order.

The stabilization method is used in conjunction with Koopmans-based approximation to calculate the energies of pi* temporary anion states of a series of substituted benzenes in density functional theory. In this approach, the Koopmans expression is corrected due to the consideration of the integer discontinuities in the exact exchange-correlation potential. Stabilization is accomplished by varying the exponents of appropriate diffuse functions. The energies of pi* states are then identified by investigating the relationship between the resultant eigenvalues and scale parameter. Results indicate that this approach can yield an improvement in the predictions of the absolute energies of pi* states over other methods.

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