Paper on fullerene anion chemistry accepted by Chemical Science

Hydrocarbon-soluble, hexaanionic fulleride complexes of magnesium
Chem. Sci., Accepted.
Samuel R. Lawrence,  C. André Ohlin, David B. Cordes,  Alexandra M. Z. Slawin, Andreas Stasch

Abstract: The reaction of the magnesium(I) complexes [{( Arnacnac)Mg}2], ( Arnacnac = HC(MeCNAr)2 , Ar =Dip (2,6-iPr2C6H3), Dep (2,6-Et2C6H3), Mes (2,4,6-Me3C6H2), Xyl (2,6-Me2C6H3 )) with fullerene C60 afforded a series of hydrocarbon-soluble fulleride complexes [{(Arnacnac)Mg}nC60], predominantly with n = 6, 4 and 2. 13C{1H} NMR spectroscopic studies show both similarities (n = 6) and differences (n = 4, 2) to previously characterised examples of fulleride complexes and materials with electropositive metal ions. The molecular structures of[{(Arnacnac)Mg}nC60] with n = 6, 4 and 2 can be described as inverse  coordination complexes of n [(Arnacnac)Mg]+ ions with C60n- anions showing predominantly ionic metal-ligand interactions, and include the first well-defined and soluble complexes of the C606- ion. Experimental studies show the flexible ionic nature of the {(Arnacnac)Mg}+····C606-  coordination bonds. DFT calculations on the model complex [{(Menacnac)Mg}6C60] (Menacnac = HC(MeCNMe)2) support the formulation as an ionic complex with a centralC606- anion and comparable frontier orbitals toC606- with a small HOMO-LUMO gap. The reduction of C60 to its hexaanion gives an indication about the reducing strength of dimagnesium(I) complexes.

Paper on smectite hydration accepted by ACS Earth and Space Chemistry

Deconvolution of Smectite Hydration Isotherms

Authors: Jerry Lindholm, Jean-Francois Boily and Michael Holmboe.
Link: doi.org/10.1021/acsearthspacechem.9b00178
Synopsis:
Sorption isotherm models have traditionally served as an invaluable tool to characterize synthesized and natural mineral particles, but often fail to describe the behavior of swelling materials. This research presents a novel composite isotherm model that describes water uptake by adsorption, step-wise intercalation, and condensation.

Paper on microwave synthesis accepted by European Journal of Inorganic Chemistry

Microwave Synthesis of Alkali-Free Hexaniobate, Decaniobate, and Hexatantalate Polyoxometalate Ions
in Eur. J. Inorg. Chem.201935, 3913-3918.   Link
M. A. Rambaran, M. Pascual-Borràs and C. A. Ohlin

Abstract:
 Microwave synthesis of polyoxoniobates and -tantalates circumvents the prolonged heating required by conventional hydrothermal methods, while providing comparable or greater yields. Microwave irradiation allows synthesis of polyoxoniobates from anhydrous niobium pentoxide, in lieu of niobic acid and sets the precedent for the discovery of new polyoxoniobates and -tantalates.

Sapphire-supported water films: Paper with PNNL collaborators just accepted in JCIS

In collaboration with Hongfei Wang (Fudan University) and other current and former Pacific Northwest National Laboratory scientists, we used Sum Frequency Generation Vibrational Spectroscopy (SFG-VS) and molecular model to provide new insight on the orientation and hydrogen bond populations of nanometric water films on sapphire (alpha-Al2O3) surfaces:

J.-F. Boily*, L. Fu., A. Tuladhar, Z. Lu, Z.M., Legg B., Wang, H.-F. Wang (2019). Hydrogen Bonding and Molecular Orientations Across Thin Water Films on Sapphire. J. Colloid Interface Sci. (accepted)

 

 

 

Clays, New Perspectives, Challenges & Opportunities workshop at MIT

Michae Holmboe gave an invited talk on the characterization of clay microstructure and molecular dynamics simulations – at the workshop “Clays, New Perspectives, Challenges & Opportunities”, May 2-3 2019, hosted by Prof Andrew Whittle and his postdoc Ali Seiphoori at the Massachusetts Institute of Technology (MIT). Read more here: clays.mit.edu