ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Magnetic, Spectral, and Thermal Characterization of 2,3,4- and 3,4,5-Trimethoxybenzoates of Mn(II), Co(II), Ni(II), and Cu(II)

W. Ferenc, B. Bocian, A. Walków-Dziewulska, and J. Sarzyński

Faculty of Chemistry, Maria Curie-Sklodowska University, PL-20 031, Lublin, Poland

E-mail: wetafer@hermes.umcs.lublin.pl

Received: 7 September 2004

Abstract: The physicochemical properties and thermal stability in air of 2,3,4- and 3,4,5-trimethoxybenzoates of Mn(II), Co(II), Ni(II), and Cu(II) were compared and the influence of the position of —OCH3 substituent on their thermal stability and magnetic properties was investigated. The complexes of these series are crystalline, hydrated or anhydrous salts with colours typical of M²⁺ ions. The carboxylate ion is a monodentate and bidentate chelating or bridging group. The thermal stability of complexes was studied in the temperature range of 293—1273 K. The solubility in water at 293 K for these analyzed complexes is in the order of 10⁻³—10⁻⁴ mol dm⁻³ for 2,3,4-trimethoxybenzoates and 10⁻²—10⁻⁴ mol dm⁻³ for 3,4,5-trimethoxybenzoates. The magnetic susceptibilities for trimethoxybenzoates were measured over the range of 76—303 K and their magnetic moments were calculated. The results show that compounds of Mn(II), Co(II), and Ni(II) are high-spin complexes but those of Cu(II) form dimers.

Full paper in Portable Document Format: 595a316.pdf

Chemical Papers 59 (5) 316–323 (2005)