Magnetic and structural studies of vanadium arene complexes

The temperature dependence of the solid-state magnetic susceptibility for the paramagnetic V(I) complexes trans-(CpV)2(μ-n 6:n6-C6H6) (1) and CpV(n 6-C6H6) (2) has been investigated. Complex 1 obeys the Curie-Weiss law over the temperature range 10-300 K with μ eff = 4.81 μB and Θ = -18.8 K. The hig...

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Hlavní autoři: Beck, V, Cowley, A, O'Hare, D
Médium: Journal article
Jazyk:English
Vydáno: 2004
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author Beck, V
Cowley, A
O'Hare, D
author_facet Beck, V
Cowley, A
O'Hare, D
author_sort Beck, V
collection OXFORD
description The temperature dependence of the solid-state magnetic susceptibility for the paramagnetic V(I) complexes trans-(CpV)2(μ-n 6:n6-C6H6) (1) and CpV(n 6-C6H6) (2) has been investigated. Complex 1 obeys the Curie-Weiss law over the temperature range 10-300 K with μ eff = 4.81 μB and Θ = -18.8 K. The high-temperature moment is consistent with the presence of a total of four unpaired electrons derived from two low-spin V(I) d4 metal centers in an S = 2 configuration. However, at ca. 9 K the magnetic susceptibility displays a broad maximum. This magnetic behavior may be modeled over the full temperature range (4-300 K) using the Heisenberg intracluster magnetic exchange expression for an S1 = S2 = 1 system with g = 2.37, Θ = -12.3 K, and J = -2.64 cm-1. Complex 2 obeys the Curie-Weiss law over the temperature range 5-300 K, with μeff = 2.86 μB and Θ = -5.0 K. The X-ray structure of 2 (P2 1/a, a = 10.7842(4) Å, b = 7.8233(4) Å, c = 11.2017(5) Å, β= 113.830(2)° at 150 K, Z = 4) has been determined. Crystals of 2 undergo a reversible phase transition to a new monoclinic cell with a' ≈ (a + c)/2, b' ≈' b, c' ≈ (c -a)/2 over the temperature range 290-270 K.
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spelling oxford-uuid:f8aecffc-e999-442e-bc9c-e8d74916f01a2022-03-27T12:52:09ZMagnetic and structural studies of vanadium arene complexesJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:f8aecffc-e999-442e-bc9c-e8d74916f01aEnglishSymplectic Elements at Oxford2004Beck, VCowley, AO'Hare, DThe temperature dependence of the solid-state magnetic susceptibility for the paramagnetic V(I) complexes trans-(CpV)2(μ-n 6:n6-C6H6) (1) and CpV(n 6-C6H6) (2) has been investigated. Complex 1 obeys the Curie-Weiss law over the temperature range 10-300 K with μ eff = 4.81 μB and Θ = -18.8 K. The high-temperature moment is consistent with the presence of a total of four unpaired electrons derived from two low-spin V(I) d4 metal centers in an S = 2 configuration. However, at ca. 9 K the magnetic susceptibility displays a broad maximum. This magnetic behavior may be modeled over the full temperature range (4-300 K) using the Heisenberg intracluster magnetic exchange expression for an S1 = S2 = 1 system with g = 2.37, Θ = -12.3 K, and J = -2.64 cm-1. Complex 2 obeys the Curie-Weiss law over the temperature range 5-300 K, with μeff = 2.86 μB and Θ = -5.0 K. The X-ray structure of 2 (P2 1/a, a = 10.7842(4) Å, b = 7.8233(4) Å, c = 11.2017(5) Å, β= 113.830(2)° at 150 K, Z = 4) has been determined. Crystals of 2 undergo a reversible phase transition to a new monoclinic cell with a' ≈ (a + c)/2, b' ≈' b, c' ≈ (c -a)/2 over the temperature range 290-270 K.
spellingShingle Beck, V
Cowley, A
O'Hare, D
Magnetic and structural studies of vanadium arene complexes
title Magnetic and structural studies of vanadium arene complexes
title_full Magnetic and structural studies of vanadium arene complexes
title_fullStr Magnetic and structural studies of vanadium arene complexes
title_full_unstemmed Magnetic and structural studies of vanadium arene complexes
title_short Magnetic and structural studies of vanadium arene complexes
title_sort magnetic and structural studies of vanadium arene complexes
work_keys_str_mv AT beckv magneticandstructuralstudiesofvanadiumarenecomplexes
AT cowleya magneticandstructuralstudiesofvanadiumarenecomplexes
AT ohared magneticandstructuralstudiesofvanadiumarenecomplexes