2013-05-26 06:25:01 1281 Pradip Chakraborty, Robert Bronisz, Céline Besnard, Laure Guénée, Phil Pattison and Andreas Hauser Chakraborty, Pradip Bronisz, Robert Besnard, Céline Guénée, Laure Pattison, Phil Hauser, Andreas Journal of the American Chemical Society J. Am. Chem. Soc. 0002-7863 2012 134 4049 4052 H http://pubs.acs.org/doi/abs/10.1021/ja211897t http://pubs.acs.org/doi/full/10.1021/ja211897t http://pubs.acs.org/doi/pdf/10.1021/ja211897t In the covalently linked 2D coordination network {[Fe(bbtr)₃](BF₄)₂}_∞, bbtr = 1,4-di(1,2,3-triazol-1-yl)butane, the iron(II) centers stay in the high-spin (HS) state down to 10 K. They can, however, be quantitatively converted to the low-spin (LS) state by irradiating into the near-IR spin allowed ⁵dd band and back again by irradiating into the visible ¹dd band. The compound shows true light-induced bistability below 100 K, thus, having the potential for persistent bidirectional optical switching at elevated temperatures.

]]> H332I564P788 10.1021/ja211897t 18789 http://www.unige.ch/sciences/chifi/publis/pics/double/ref01281.png http://www.unige.ch/sciences/chifi/publis/refs_pdf/ref01281.pdf 1228 Lilit Aboshyan-Sorgho, Céline Besnard, Phil Pattison, Kevin R. Kittilstved, Annina Aebischer, Jean-Claude G. Bünzli, Andreas Hauser, Claude Piguet Aboshyan-Sorgho, Lilit Besnard, Céline Pattison, Phil Kittilstved, Kevin R. Aebischer, Annina Bünzli, Jean-Claude G. Hauser, Andreas Piguet, Claude Angewandte Chemie International Edition Angew. Chem. Intl. Ed. 1433-7851 2011 50 4108 4112 H helical structures;lanthanides;photochemistry;self-assembly;upconversion helical structures lanthanides photochemistry self-assembly upconversion http://onlinelibrary.wiley.com/doi/10.1002/anie.201100095/abstract;jsessionid=C352764B1E9229A45C8C5FB9AEA7917B.d02t01 http://onlinelibrary.wiley.com/doi/10.1002/anie.201100095/pdf The connection of two Cr^III sensitizers around a central Er^III acceptor in a self-assembled cation provides high local metal concentrations that favor efficient nonlinear energy transfer upconversion luminescence (see picture). Upon selective low-energy near-infrared irradiation of Cr^III-centered transitions, 1 displays an unprecedented molecular two-photon upconverted green Er^III-centered emission.

]]> H210I421P653V 10.1002/anie.201100095 15714 http://www.unige.ch/sciences/chifi/publis/pics/double/ref01228.png http://www.unige.ch/sciences/chifi/publis/refs_pdf/ref01228.pdf 638 Patrick Franz, Christina Ambrus, Andreas Hauser, Dmitry Chernyshov, Marc Hostettler, Jürg Hauser, Lukas Keller, Karl Krämer, Helen Stoeckli-Evans, Philip Pattison, Hans-Beat Bürgi, and Silvio Decurtins Franz, Patrick Ambrus, Christina Hauser, Andreas Chernyshov, Dmitry Hostettler, Marc Hauser, Jürg Keller, Lukas Krämer, Karl Stoeckli-Evans, Helen Pattison, Philip Bürgi, Hans-Beat Decurtins, Silvio Journal of the American Chemical Society J. Am. Chem. Soc. 0002-7863 2004 126 50 16472 16477 H http://pubs.acs.org/cgi-bin/abstract.cgi/jacsat/2004/126/i50/abs/ja0465451.html http://pubs.acs.org/cgi-bin/article.cgi/jacsat/2004/126/i50/html/ja0465451.html http://pubs.acs.org/cgi-bin/article.cgi/jacsat/2004/126/i50/pdf/ja0465451.pdf The compound of stoichiometry Mn(II)₃[Mn(III)(CN)₆]₂·zH₂O (z = 12−16) (1) forms air-stable, transparent red crystals. Low-temperature single crystal optical spectroscopy and single crystal X-ray diffraction provide compelling evidence for N-bonded high-spin manganese(II), and C-bonded low-spin manganese(III) ions arranged in a disordered, face-centered cubic lattice analogous to that of Prussian Blue. X-ray and neutron diffraction show structured diffuse scattering indicative of partially correlated (rather than random) substitutions of [Mn(III)(CN)₆] ions by (H₂O)₆ clusters. Magnetic susceptibility measurements and elastic neutron scattering experiments indicate a ferrimagnetic structure below the critical temperature T_c = 35.5 K.

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