Aqua Ions. 1. The Structures of the [Ru(OH₂)₆]³⁺ and [V(OH₂)₆]³⁺ Cations in Aqueous Solution:  An EPR and UV−Vis Study

Abstract

Spectroscopic data are presented for the [V(OH(2))(6)](3+) and [Ru(OH(2))(6)](3+) cations, from which inferences are drawn regarding their structures in aqueous solution. EPR and absorption spectra of solutions and glasses are supplemented by spectra of the aqua ions in various crystalline environments, and the electronic and molecular structures inter-related through elementary angular overlap model calculations. It is concluded that in aqueous solution the [Ru(OH(2))(6)](3+) cation is localized in the all-horizontal D(3)(d)geometry, whereas the structure of the [V(OH(2))(6)](3+) cation is close to T(h) symmetry. These results are consistent with the most energetically favored geometries predicted by ab initio calculations.

Spin State Crossover, Vibrational, Computational, and Structural Studies of FeII 1‐Isopropyl‐1H‐tetrazole Derivatives

“…The twist angle φ between the tetrazole ring and the N(2) O(10) N(2) O(10) plane of the FeL 6 octahedron is 25.95°. The H 2 O planes are rotated about the Fe(1)–O(4) and Fe(1)–O(5) bond vectors by twist angles φ of 51.02 and 81.61°, respectively, relative to the equatorial plane, according to the low symmetry of the coordinated water molecules . The α angle between the tetrazole ring and the plane defined by the three carbon atoms of the isopropyl group is 87.36°.…”

Structure and Dynamics of the Cd2+ Ion in Aqueous Solution: Ab Initio QM/MM Molecular Dynamics Simulation.

“…12,13,16,18,20 To our knowledge, no structural data has been evaluated for the Jahn-Teller distortions of the V 31 ion in aqueous solution. 12,13,16,18,20 To our knowledge, no structural data has been evaluated for the Jahn-Teller distortions of the V 31 ion in aqueous solution.…”

“…5 Crystal structures of the caesium alums 6 and the alkali-metal vanadium sulfate b-alums 7 were evaluated using the X-ray diffraction technique, providing the V 31 4 structure was characterized using X-ray and neutron diffraction techniques, showing the V 31 -O bond distances reported in the range of 1.988-2.003 and 1.978-2.013 Å , respectively. Several spectroscopic techniques [11][12][13][14][15][16]20 were applied to evaluate the hydration structure and spectroscopic data of the V 31 ion in b-alums and salts. 9 Using the B3LYP/6-311G*(5d,7f) level of theory, 10 the C i symmetrical arrangement represents potential energy minima for V 31 aqua ion.…”

“…The distorted octahedral of the [V(H 2 O) 6 ] 31 ion was analyzed by lowtemperature electronic spectra of NH 4 V(H 2 O) 6 (SO 4 )Á6H 2 O. 16 Recently, numerous crystal structures of the [V(H 2 O) 6 ] 31 complex in different salts were investigated by X-ray and neutron diffraction methods, 17 showing that a variation of the V 31 -O bond distances is in the range from 1.987 to 2.004 Å . 12 High-field multifrequency electron paramagnetic resonance (HF-EPR) spectroscopy has confirmed that the structure of the [V(H 2 O) 6 ] 31 complex is close to T h symmetry.…”

Structural and dynamical properties of the V3+ ion in dilute aqueous solution: An ab initio QM/MM molecular dynamics simulation

“…The aqua vanadium plays an essential role in chemical reactions and biological systems1, 2 since its complex has been used in the treatment of diabetes and cancer 3, 4. Because of the complexity of the V 3+ ion in aqueous solution, it has been an interesting area for both experimental and theoretical studies 5–18. In solution the hexahydrated V 3+ is easily oxidized 19.…”