The iron(II) sulfonates Fe(CF3SO3)2 and Fe(p-CH3C6H4SO3)2 have been prepared and on the basis of vibrational and electronic spectra and magnetic and MÖssbauer data have been assigned a layer lattice structure involving hexacoordinated iron(II) and terdentate bridging anions. The FeO6 chromophore in these compounds is distorted by a trigonal elongation along the C3 axis. Fe(CH3SO3)2 has been obtained in two isomeric forms, one having a trigonal elongation of the FeO6 chromophore, the other a trigonal compression. No structural isomerism has been found for the other iron(II) sulfonates; however, evidence for such isomerism in methanesulfonates of cobalt(II) and zinc(II) is presented. While Fe(CF3SO3)2 and Fe(p-CH3C6H4SO3)2 appear to be magnetically dilute the presence of antiferromagnetic coupling in both forms of Fe(CH3SO3)2 is indicated. The iron(III) sulfonates, Fe(CF3SO3)3, Fe(p-CH3C6H4SO3)3, and Fe(CH3SO3)3, have been prepared and all three are magnetically concentrated exhibiting magnetic moments which are significantly less than 5.92 BM and which decrease with decreasing temperature.

. 64, 429 (1986).The iron(I1) complexes Fe(NC5H5)4(RS03)2 where R = CF3, CH,, and p-CH3C6H4 have been prepared and their crystal structures determined by single crystal X-ray diffraction. Cryst$ of trans-bis(methanesulfonato-O)tetrakis(pyridine)iron(II) are monoclinic, a = 16.524(2), b = 9.1 127(6), c = 18.684(2) A, P = 109.903(6)", Z = 4, space group Pn. The structure was solved by conventional heavy-atom methods and was refined by full-matrix least-squares procedures to R = 0.034 and R,, = 0.038 for 4243 reflections with I 2 3u(4. Crystals of trans-bis(trifluoromethanesulfonato-O)tetrakis(pyridine)iron(II) are monoclinic, a = 10.456(1), b = 9.2981(8), c = 14.625(2) A, P = 96.372(6)", Z = 2, space group Pn. Structure solved and refined as above to R = 0.036, and R,, = 0.037 for 1483 reflections with 1 2 3u(4. Crystals of transbis(p-toluenesulfonato-O)tetrakis(pyridine)iron(II) are orthorhombic, a = 40.818(2), b = 9.8722(6), c = 17.3544(7) A, Z = 8, space group Fdd2. The structure was solved by Patterson and Fourier syntheses and was refined by full-matrix least-squares procedures to R = 0.030 and R,, = 0.032 for 1851 reflections with 1 2 3u(l). All three structures show discrete octahedral molecules with monodentate trans-coordinated sulfonate groups. Two crystallographically independent molecules are observed in the R = CH3 structure, the difference between them involving the orientation of the CH3S03 groups with respect to the 0-Fe-0 vector. The FeN402 chromophore in each compoundo is a tetragonally compressed octahedron (approximate D4,, Dans le trois structures, on retrouve des molCcules octaCdriques individuelles avec des groupements sulfonates monodentates coordonntes en trans. Dans la structure oh R=CH3, on observe deux moltcules qui sont cristallographiquement indtpendantes; la difftrence entre les deux implique I'orientation des groupements CH3S03 par rapport au vecteur 0-Fe-0.Dans chacun des composts, le chromophore FeN402 est un octatdre qui est comprimt d'une faqon tttragonale (symttrie approximative D4)!) et dans lequel les distances Fe-N moyennes sont 2,21, 2.23 et 2,24 A alors que les distances Fe---0 sont 2,11, 2,06 et 2,08 a respectivement pour les derives CF3, CH3 et p-CH3C6H4. On a CtudiC les composts en faisant appel aux spectroscopies vibrationnelles, tlectroniques et de Mossbauer, i des mesures de susceptibilitt magnttique et i la calorimttrie de balayage difftrentiel. Les valeurs des dtdoublements quadrupolaires obtenus a partir des spectres de Mossbauer indiquent que les trois composts existent dans un ttat fondamental 5B2,; on a analysC les donnCes de susceptibilitC magnttique (de 3 10a 4,2 K) i l'aide des modtles tant de champ cristallin que de dtdoublement i champ ztro en faisant I'hypothtse que 1'Ctat fondamental est bien celui-18.[Traduit par le journal] IntroductionWe had earlier utilized spectroscopic and magnetic techThe study of the coordinating properties of sulfonate anions, niques to investigate the coordination of Sulfonate anions in RS03-, is of interest for a number of re...

. Can. J. Chem. 65,420 (1987).Crystals of poly-bis(pyrazine)bis(methanesulfonato-O)copper(II) are orthorhombic, a = 8.199(1), b = 13.130(1), c = 6.913(1) A, Z = 2, space group Pnnm. The structure was solved by conventional heavy atom methods and was refined by full-matrix least-squares procedures to R = 0.025 and R,, = 0.033 for 1226 reflections with I 2 3u(I). The complex contains parallel sheets, each sheet consisting of a square array of copper(I1) ions bridged by two types of bidentate pyrazine ligands. The CuN402 chromophore is tetragonally elongated; the equatorial plane contains two pyrazine nitrogen atoms (Cu-N(1) = 2.058(2) A) and two oxygen atoms from monodentate methanesulfonate ligands (Cu-O(1) = 1.956(1) A); the axial sites are occupied by bridging pyrazine groups with significantly longer Cu-N bond lengths (Cu-N(2) = 2.692(2) A). Magnetic susceptibility studies (82 to 4.2 K) reveal antiferrornagnetic behaviour with a susceptibility maximum at about 6.2 K. Exchange coupling in the complex is considered to take place primarily via the more strongly bound, equatorially coordinated pyrazine ligands. Analysis of the magnetic susceptibility data according to a Heisenberg linear chain of interacting S = 1/2 spins yields best fit values of J = -3.82 cm-' and g = 2.13. Vibrational and electronic spectroscopic and differential scanning calorimetric studies on the title compound and, for comparison, on the related mononuclear pyridine complex, bis(methanesu1fonato)-tetrakis(pyridine)copper(II), are also reported. tl" = 2,692(2) ). Des Ctudes de susceptibilitt magnCtique (de 82 a 4,2 K) rCvklent l'existence d'un comportement antiferromagnCtique avec une susceptibilit6 maxirnale a environ 6,2 K. On considkre que, dans le complexe, le couplage d'tchange se produit principalement par le biais des ligands pyrazines qui sont coordonnts d'une f a~o n tquatoriale et qui sont lits plus fortement. Une analyse des donnCes de susceptibilitC magnktique, en faisant appel d'une chaine lintaire de Heisenberg des spins S = 1/2 qui interagissent, conduit A des valeurs de J = -3,82 cm-' et g = 2,13. On rapporte aussi les Ctudes spectroscopiques, tant au niveau vibrationnel qu'Clectronique, ainsi que les ttudes calorimCtriques B balayage difftrentiel qui ont t t t faites sur le compos mentionnt dans le titre et, pour fins de comparaison, sur le complexe pyridine mononucltaire apparentC, bis(mCthanesulfonato)tttrakis(pyridine)cuivre(II).[Traduit par la revue] IntroductionPyrazine-bridged complexes of the transition metals are of particular interest because of the potential for the propagation of magnetic exchange over extended distances, and some of the most fruitful investigations in this area have involved complexes of copper(I1). Extensive structural and magnetic studies on complexes such as C~( p y z )~( C l O~)~ (1, 2), C u ( p y~) ( N o~)~ (3) and the hexafluoroacetylacetonate analogue, Cu(pyz)(hfac), (4) have shown that the magnitude of the exchange coupling in these systems is significantly affected by structural variati...

No abstract

Can. J. Chem. 62, 891 (1984).The preparation, magnetic and thermal properties, electronic and infrared spectra. and molecular structure of poly-bis(pdi-n-hexylphosphinato)copper(II) are described. Crystals of the compound are triclinic, a = 9.800(3), b = 12.336(6), c = 13.352(8) A, a = 88.53(3), P = 74.02(4), y = 82.33(3)", Z = 2, space group P I . The structure was solved by Patterson and Fourier syntheses and was refined by full-matrix least-squares procedures to R = 0.045 and R,,. = 0.056 for 3095 reflections with I 2 3o(I). The crystal structure of C U [ (~-C~H ,~)~P O~]~ consists of well-separated infinite chains of centrosymmetric spiro-fused eight-membered rings propagating along the crystallographic a axis.The magnetic susceptibility of C U [ (~-C~H , ,~)~P O~]~ was studied over the temperature range 4.2 to 300 K. The compound shows ferromagnetic behaviour and the data have been successfully analyzed according to the isotropic Heisenberg model for linear chains with g = 2.16 and J = 2.58 cm-'. For comparison, the magnetic susceptibilities of CU[(C,H~),PO,]~ and C U [ (~-C , H~) , P O~]~ have also been measured over the range 4.2 to 300 K. The butyl derivative shows ferromagnetic exchange with g = 2.16 and J = 2.22 cm-' while the ethyl derivative is antiferromagnetic with g = 2.19 and -J = 1.27 cm-'. The structural details of all three compounds are examined in the light of the differing magnetic properties. . Can. J. Chem. 62, 891 (1984). On dCcrit les propriCtts magnCtiques et thermales, les spectres Clectronique et infrarouge, et la structure molCculaire de poly-bis(p-!i-n-hexyle phosphinato) cuivre(I1). Les cristaux sont tricliniques, a 9,800(3), b = 12,336(6), c = L3,352(8) A, a = 88,53(3), P = 74,02(4), y = 82,33(3)", Z = 2, groupe d'espace P I . On a rCsolu la structure par les syntheses de Patterson et de Fourier et on l'a affinCe par la mCthode des moindres carrCs (matrice entiere) jusqu'a des valeurs de R = 0,045 et R,,. = 0,056 pour 3095 reflexions avec I 2 3u(1). La structure du cristal de consiste en chainons, infinis et bien stpares, des cycles de huit membres, centrosymmetriques et spiro-fustes, qui sont propages suivant l'axe c . On a Ctudit la susceptibilitC magnitique dans I'intervalle de tempkrature de 4.2 i 300 K. La composC prCsente les proprittts ferromagnktiques et on a analyst les donntes d'aprbs la modble isotropique de Heisenberg pour les chainons lintaires, avec g = 2,16 et J = 2,58 cm-'. Par comparaison, les susceptibilitCs magnktiques de C U [ ( C , H~)~P O~]~ et de C U [ (~-C~H~)~P O~]~ ont t t t mesurCs aussi dans I'intervalle 4,2 a 300 K. Le dCrivatif butylique exhibe 1'Cchange ferromagnttique, avec g = 2,16 et J = 2,22 cm-', tandis que le dtrivatif CthylC est antiferromagnttique avec g = 2.19 et -J = 1,27 cm-'. On a examine les particularitCs structurales de tous les trois composCs en vue des proprittks magnttiques difftrentes. IntroductionSingle crystal X-ray diffraction studies on C U [ ( C~H~)~P O~]~ (1) and CU[(~-C,H,)~PO~]~ (2) have shown them to be polymeric with we...