Theoretical description of the magnetic properties of μ3-hydroxo bridged trinuclear copper(II) complexes

• Published in: Journal of molecular modeling 2013-07, Vol.19 (7), p.2835-2844
• Main Authors: Cañon-Mancisidor, Walter, Spodine, Evgenia, Paredes-Garcia, Veronica, Venegas-Yazigi, Diego
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Computer Appl. in Life Sciences; Computer Applications in Chemistry; Copper - chemistry; Crystallography, X-Ray; Electron Spin Resonance Spectroscopy; Magnetics; Molecular Medicine; Molecular Structure; Original Paper; Pyrazoles - chemistry; Theoretical and Computational Chemistry; Triazoles - chemistry
• ISSN: 1610-2940; 0948-5023
• DOI: 10.1007/s00894-012-1696-5

A theoretical study of the magnetic properties, using density functional theory, of a family of trinuclear μ 3 -OH copper(II) complexes reported in the literature is presented. The reported X-ray crystal structures of [Cu 3 (μ 3 -OH)(aat) 3 (H 2 O) 3 ](NO 3 ) 2 ·H 2 O ( HUKDUM ), where aat: 3-acetylamine-1,2,4-triazole; [Cu 3 (μ 3 -OH)(aaat) 3 (H 2 SO 4 )(HSO 4 )(H 2 O)] ( HUKDOG ), where aaat: 3-acetylamine-5-amine-1,2,4-triazole; [Cu 3 (μ 3 -OH)(PhPyCNO) 3 (tchlphac) 2 ] ( HOHQUR ), where PhPyCNO: phenyl 2-pyridyl-ketoxime and tchlphac: acid 2,4,5-trichlorophenoxyacetic; [Cu 3 (μ 3 -OH)(PhPyCNO) 3 (NO 3 ) 2 (CH 3 OH)] ( ILEGEM ); [Cu 3 (μ 3 -OH)(pz) 3 (Hpz) 3 (ClO 4 ) 2 ] ( QOPJIP ), where Hpz = pyrazole; [Cu 3 (μ 3 -OH)(pz) 3 (Hpz)(Me 3 CCOO) 2 ]∙2Me 3 CCOOH ( DEFSEN ) and [Cu 3 (μ 3 -OH)(8-amino-4-methyl-5-azaoct-3-en-2-one) 3 ][CuI 3 ] ( RITXUO ), were used in the calculations. The magnetic exchange constants were calculated using the broken-symmetry approach. The calculated J values are for HUKDUM J 1  = −68.6 cm −1 , J 2  = −69.9 cm −1 , J 3  = −70.4 cm −1 ; for HUKDOG , J 1  = −73.5 cm −1 , J 2  = −58.9 cm −1 , J 3  = −62.1 cm −1 ; for HOHQUR J 1  = −128.3 cm −1 , J 2  = −134.1 cm −1 , J 3  = −120.4 cm −1 ; for ILEGEM J 1  = −151.6 cm −1 , J 2  = −173.9 cm −1 , J 3  = −186.9 cm −1 ; for QOPJIP J 1  = −118.3 cm −1 , J 2  = −106.0 cm −1 , J 3  = −120.6 cm −1 ; for DEFSEN J 1  = −74.9 cm −1 , J 2  = −64.0 cm −1 , J 3  = −57.7 cm −1 and for RITXUO J 1  = −10.9 cm −1 , J 2  = +14.3 cm −1 , J 3  = −35.4 cm −1 . The Kahn-Briat model was used to correlate the calculated magnetic properties with the overlap of the magnetic orbitals. Spin density surfaces show that the delocalization mechanism is predominant in all the studied compounds. Figure The Kahn-briat model was used to correlate the calculated magnetic properties with the overlap of the magnetic orbitals.