The crystal structures of (BEDT–TTF)2[MHg(SCN)4] (M=K at 298 and 104 K and M=NH4 at 298 K) were determined by X-ray analyses. A donor layer and an anion sheet stack alternately along the b-axis. The packing pattern of the donor is close to α-phase, while an anion sheet constructs a thick two-dimensional polymer plane parallel to (010). The linkage of (Remark: Graphics omitted.) (or NH4) (Remark: Graphics omitted.) in an anion sheet is very unique. The band structure calculation indicates both a closed and an open Fermi surfaces, resembling that of κ-(BEDT–TTF)2[Cu(NCS)2].

Combinatorial laser molecular-beam epitaxy method was employed to fabricate epitaxial Zn1−xMnxO thin films in a high throughput fashion. Local structures around Mn were investigated for these c-axis-oriented epitaxial films by fluorescence x-ray absorption fine structure measurements. It was shown that Mn substitutionally replaces Zn in Zn1−xMnxO (x<0.22) films. Well-structured blue and ultraviolet cathodoluminescence peaks corresponding to the intra-d-shell transitions of Mn2+ were observed, especially for smaller x. The luminescence is quenched rapidly as x is increased. By comparing the relative absorption strength per mole Mn2+ with the statistical probability of isolated Mn2+, it was concluded that the quick decrement of isolated Mn2+ with increasing x is responsible for the severe suppression of the blue and ultraviolet luminescence.

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The electrochemical oxidation of BEDT-TTF with Hg(SCN)2, KSCN, and 18-crown-6 ether yielded two different BEDT-TTF salts of mercury(II) thiocyanate depending on the solvent used. The K+ containing salt, (BEDT-TTF)2[KHg(SCN)4], was metallic down to 1.5 K with various temperature dependences. The crystal structures showed an alternating stacking of two-dimensional networks of BEDT-TTF molecules and of KHg(SCN)4 anions. The other modification (BEDT-TTF)3[Hg(SCN)3] exhibited metal-insulator (MI) transition at around 180 K.

We have investigated the electronic structure of Zn1−xMxO (M: 3d transition metal) by x-ray absorption spectroscopy. Using configuration–interaction cluster-model analyses, electronic structure parameters have been deduced and their chemical trend is discussed. Results show that the p–d exchange constant Nβ is negative and large in cases of Mn, Fe, and Co, which is consistent with the enhancement of magnetic circular dichroism.