B.S., University of New Hampshire, 1978
M.S., University of New Hampshire, 1984
Ph.D., Brandeis University, 1987
Visiting Lecturer, University of Canterbury, Christchurch, NZ 1995
Visiting Professor, Universitat de Barcelona, Spain 2001-2002 Current ResearchOur research lies in the preparation of new materials and is focused in two areas. Molecular Magnetism
Over the last two decades, a new field of research has emerged called molecular magnetism. The guiding principle is to use our understanding of structure, bonding and geometry to control the bulk magnetic properties of a material at the molecular level. This is highly interdisciplinary work and involves teams of collaborating organic and inorganic chemists, theoreticians and condensed physicists (our group works in collaboration with that of Prof. Christopher Landee in the Physics Dept. as well as several groups around the world, including Spain, Germany, Great Britain and New Zealand). 
Low-dimensional Antiferromagnets
The copper oxide-based high temperature superconductors have introduced a new era to the field of conducting materials, but the mechanism of their superconductivity is still not well understood. One theory suggests that the mechanism of the electrical superconductivity is relted to the mechanism of magnetic super-exchange in these compounds. We are working to prepare structurally related complexes which have more moderate ordering tempertures as models for these systems and others where the magnetic interactions are not principally propagatged in 3-dimensions. Of special interests are those materials where the magnetic interactions are not strictly one- or two-dimensional in nature, but whose topology may be described as inter-dimensional, such as ladders, honeycombs and rectangles. We have recently succeeded in preparing a large family of the best examples of magnetic ladders known (at right) and experiments are in progress to determine their properties and whether doping the systems will generate superconducting materials as predicted by theory. Molybdenum-Phosphine Cage Complexes: Synthesis, Characterization, and Reactivity
A number of bis-dialkylaminophosphine oxides [(R2N)2P(O)H] react with molybdenum hexacarbonyl to generate inorganic cage complexes that are structural analogues of adamantane. The nature of the alkyl substituents has a key role on the synthesis of these complexes and their subsequent reactivity. The complexes themselves may be oxidized with halogens to yield mixed valence complexes and their fully oxidized counterparts which undergo metathesis reactions with both organic and inorganic anions. Recent work has shown that the oxidized cage complexes act as coupling reagents for organic anions. We are investigating the preparation of a wide variety of these materials, their oxidation products and their use as organometallic fragments for metal-directed organic synthesis. Selected PublicationsShapiro, A.*; Landee, C.P.; Turnbull, M.M.; Jornet, J.; Deumal, M.; Novoa, J.J.; Robb, M.; Lewis, W. J. Am. Chem. Soc. 2007, 129, 952-9. "Synthesis, Structure and Magnetic Properties of an Antiferromagnetic Ladder Complex: bis(2,3-dimethylpyridinium) tetrabromocuprate."
Sologubenko, A.V.; Berggold, K.; Lorenz, T.; Rosch, A.; Shimshoni, E.; Phillips, M.D.*; Turnbull, M.M. Phys. Rev. Lett. 2007, 98, 107201. "Magnetothermal transport in the spin ½ chains of copper pyrazine dinitrate."
Schneider, R.T.*; Landee, C.P.; Turnbull, M.M.; Awwadi, F.F.; Twamley, B. Polyhedron 2007, 26, 1849-58. "Copper Azine Compounds: Synthesis, Structure and Magnetic Properties of Cu(phenazine)Cl2,
(Phenazinium)2CuCl4 and [Cu(phenazine)Cl2•H2O]2."
Woodward, F.M.#; Gibson, P.J.*; Jameson, G.; Landee, C.P.; Turnbull, M.M.; Willett, R.D. Inorg. Chem. 2007, 46, 4256-66. "Syntheses. X-ray structures and Magnetic Behavior of [Cu(pz)2](ClO4)2, [Cu(pz)2](BF4)2 and [Cu(pz)2(NO3)](PF6)."
Li, L.#; Turnbull, M.M.; Landee, C.P.; Jornet, J.; Deumal, M.; Novoa, J.J.; Wikaira, J.L. Inorg. Chem. 2007, 46, 11254-65. "Synthesis, structure and magnetic behavior of bis(2-amino-5-fluoropyridinium) tetrachlorocuprate(II)."
Parent, A.R.*; Vedachalam, S.&; Landee, C.P.; Turnbull, M.M. J. Coord. Chem. 2008, 61, 93-108 (cover article). "Syntheses, Crystal Structures and Magnetic Properties of Heteronuclear Bimetallic Compounds of
[Cu(pdc)2][M(H2O)5]•2H2O [M=Ni(II), Co(II), Mn(II); pdc = 2,6-pyridinedicarboxylato]."
Sologubenko, A.V.; Lorenz, T.; Mydosh, J.A.; Rosch, A.; Shortsleeves, K.C.*; Turnbull, M.M.. Phys. Rev. Lett. 2008, 100, 137202. "Field-dependent thermal transport in the Haldane chain compound NENP."
Herringer, S.N.*; Turnbull, M.M.; Landee, C.P.; Wikaira, J.L. J. Coord. Chem. 2009, 62, 863-75 (cover article). "Synthesis, Structure, and Magnetic Properties of Bis(3-amino-2-chloropyridinium) tetrahalocuprate (II) [halide=Cl or Br]."
Butcher, R.T.#; Turnbull, M.M.; Landee, C.P.; Wells, B.M.*; Novoa, J.J.; Ribas-Ariffio, J.; Sandvik, A.W.; Awwadi, F.F. Chem. Comm. 2009, 1359-61. "Strong Through-space Two-halide Magnetic Exchange of 2J = -234(1) K in (2,5-Dimethylpyrazine)copper(II) Bromide."
Xiao, F.#; Woodward, F.M.#; Landee, C.P.; Turnbull, M.M.; Mielke, C.; Harrison, N.; Lancaster, T.; Blundell, S.J.; Baker, P.J.; Babkevich, P.; Pratt, F.L. Phys. Rev. B, 2009, 79, 134412. "Observation of 2D XY Behavior in quasi-2D Quantum Heisenberg Antiferromagnets."
Shortsleeves, K.C.*; Dawe, L.N.; Landee, C.P.; Turnbull, M.M. Inorg. Chim. Acta 2009, 362, 1859-66. "Transition metal complexes of 2-amino-3,5-dihalopyridines: Synthesis, structures and magnetic properties of Cu(3,5-diCAP)2X2 and Cu(3,5-diBAP)2X2."
*Clark Undergraduate Student
#Clark Graduate Student
&High School Student conducting research at Clark |
