The introduction of ferromagnetic order in ZnO results in a transparent piezoelectric ferromagnet and further expands its already wide range of applications into the emerging field of spintronics. Through an analysis of density functional calculations we determine the nature of magnetic interactions for transition metals doped ZnO and develop a physical picture based on hybridization, superexchange, and double exchange that captures chemical trends. We identify a crucial role of defects in the observed weak and preparation sensitive ferromagnetism in ZnO:Mn and ZnO:Co. We predict and explain co-doping of Li and Zn interstitials to both yield ferromagnetism in ZnO:Co, in contrast with earlier insights, and verify it experimentally.

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Bile acid derivatives functionalized at the 3-position with an aromatic group formed gels in organic solvents in the presence of trinitrofluorenone.

MnO 3 show insulator-metal transitions on the passage of small electrical currents. That such an electric-field-induced transition occurs even in Y 0.5 Ca 0.5 MnO 3 where the charge-ordered state is not affected by magnetic fields is noteworthy. The transition is attributed to the depinning of the randomly pinned charge solid. These materials also exhibit an interesting memory effect probably due to the randomness of the strength as well as the position of the pinning centers.

A new class of alkyl-chain-appended pyrene derivatives 4-14 were synthesized and evaluated for their gelation abilities. Depending on the nature of the linking group, these compounds gelated a number of organic solvents, either in the presence or in the absence of the acceptor molecule 2,4,7-trinitrofluorenone (TNF). Compounds with ester, ether, or alkyl linkages gelated a number of hydroxylic and hydrocarbon solvents by means of a charge-transfer interaction with TNF, while compounds with amide, urethane and urea linkers formed gels on their own in a variety of solvents by means of pi-pi stacking and hydrogen-bonding interactions. The Xray crystal structure of urethane (S)-12 showed hydrogen-bonding and stacking features, as suggested by the model. The gels obtained were investigated by spectroscopic and electron microscopic techniques which provided structural insights.