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Abstract: Density functional calculations with the B3LYP functional were carried out for the [Ru(NO)Cl5]2−, [Ru(NO)(NH3)5]3+, [Ru(NO)(CN)5]2−, [Ru(NO)(CN)5]3−, [Ru(NO)(hedta)] q (hedta= N-(hydroxyethyl)ethylenediaminetriacetate triple-charged anion; q =0,−1,−2), Rh2(O2CR)4, Rh2(O2CR)4(NO)2, Ru2(O2CR)4, Ru2(O2CR)4(NO)2, Ru2(dpf)4, and Ru2(dpf)4(NO)2 (dpf= N,N′-diphenylformamidinate ion; R=H, CH3, CF3) complexes. The electronic structure was analyzed in terms of Mayer and Wiberg bond order indices. The technique of bond order indices decomposition into σ-, π-, and δ-contributions was proposed. [Copyright &y& Elsevier]

Abstract: The time course of gravicurvature of 3-day-old wheat (Triticum aestivum L., cv. Apogee) coleoptiles and 7-day-old wheat stems were studied in darkness and under red and red-blue light illumination after declination from the vertical at various angles. The experiments showed that the shortest gravitropic curvature corresponded to 30° initial angle of gravistimulation (IAG). The time course became longer as the IAG increased and with plant age. The effects of unilateral red (660nm) and red-blue light (660nm; 470nm) at photosynthetic photon flux (PPF) of 30μmolm−2 s−1 on the curvature of 3-day-old coleoptiles were evaluated. Red light did not produce phototropic bending of wheat coleoptiles in contrast with red-blue light. The analysis of experimental data showed that the curvature in response to a gravitropic stimulus or to combined gravity-light stimuli were not statistically different. Time course of gravitropic curvature were used to determine the acceptable crop rotation rate around the horizontal axis. Approximation of stem bending to a linear dynamic system described by a first-order aperiodic element with a lag allowed the determination of the dependence of the amplitude of apex oscillations on the rate of horizontal rotation under 1-g conditions. The calculated lowest minimal rotation rate (MRR) minimizing the gravitropic effects on wheat was about 1 revolution per hour (rph). Rotating the plant growth chamber (PGC) at a rate of more than MRR eliminated the effect of gravitropic curvature. [ABSTRACT FROM AUTHOR]

The hyperfine structure splitting in the 6 p 3 S 3 / 2 4 → 6 p 2 7 s P 1 / 2 4 transition at 307 nm in atomic 208 Bi was measured with collinear laser spectroscopy at ISOLDE, CERN. The hyperfine A and B factors of both states were determined with an order of magnitude improved accuracy. Based on these measurements, theoretical input for the hyperfine structure anomaly, and results from hyperfine measurements on hydrogen-like and lithium-like 209 Bi 80+,82+ , the nuclear magnetic moment of 208 Bi has been determined to μ ( Bi 208 ) = + 4.570 ( 10 ) μ N . Using this value, the transition energy of the ground-state hyperfine splitting in hydrogen-like and lithium-like 208 Bi 80+,82+ and their specific difference of −67.491(5)(148) meV are predicted. This provides a means for an experimental confirmation of the cancellation of nuclear structure effects in the specific difference in order to exclude such contributions as the cause of the hyperfine puzzle , the recently reported 7- σ discrepancy between experiment and bound-state strong-field QED calculations of the specific difference in the hyperfine structure splitting of 209 Bi 80+,82+ . [ABSTRACT FROM AUTHOR]

• High-resolution spectroscopy. • Coupled channels deperturbation. • Hyperfine structure. • Relativistic ab initio calculations. Laser-induced fluorescence spectra of the c 3 Σ + (v c , J c = N c) → a 3 Σ + (v a , N a = J c ± 1) transitions excited from the ground X 1 Σ + state of 39 K 133 Cs molecule were recorded with Fourier-transform spectrometer IFS125-HR (Bruker) at the highest achievable spectral resolution of 0.0063 cm − 1. Systematic study of the hyperfine structure (HFS) of the a 3 Σ + state for levels with v a ∈ [ 0 , 27 ] and N a ∈ [ 24 , 90 ] shows that the splitting monotonically increases with v a. The spectroscopic study was supported by ab initio calculations of the magnetic hyperfine interaction in X 1 Σ + and a 3 Σ + states. The discovered variation of the electronic matrix elements with the internuclear distance R is in a good agreement with the observed v a -dependencies of the HFS. Overall set of available experimental data on the a 3 Σ + state was used to improve the potential energy curve particularly near a bottom, providing the refined dissociation energy D e = 267.21 (1) cm − 1. The ab initio HFS matrix elements, combined with the empirical X 1 Σ + and a 3 Σ + PECs in the framework of the invented coupled-channel deperturbation model, reproduce the experimental term values of both ground states within 0.003 cm − 1 accuracy up to their common dissociation limit. [ABSTRACT FROM AUTHOR]