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The V-shape correlation between hvcr and ΔEo,r of the charge transfer complexes is convenient to judge the gross features of the solid state properties. Using this correlation, we found the 3:2 charge transfer complex of bis(ethylenedithio)dithiapyrene (ETDTPY) and dibenzobarrelenotetracyanoquinodimethane (DBBTCNQ) which showed the columnar structure of alternating trimeric stack of the donor and dimeric stack of the acceptor.

The crystal structure of (DMtTSF)2ReO4 (2 C11H12Se41⁄2+·ReO4−) was determined at room temperature. The structure is monoclinic, space group C2/c, with cell dimensions a=28.518(2), b=7.327(1), c=14.364(1) A β=109.84(1)°, Z=4. The DMtTSF molecules stack along the b axis to form a zigzag column. The interstack contacts between Se atoms are shorter than those in (TMTSF)2X. These contacts indicate that (DMtTSF)2ReO4 has a higher two-dimensional character than (TMTSF)2X.

X-Ray and optical reflection measurements of (DBTTF)2-(Cu2Cl6) single crystals were carried out. The single crystal of the complex consists of stacking columns of the cation molecules DBTTF+. The analysis of the reflection spectra of (DBTTF)2-(Cu2Cl6) single crystals shows that the electronic structure of DBTTF+ cation molecules is typical of the dimer type configuration.

The crystal structures of an organic superconductor (BEDT-TTF)2Cu(NCS)2 (Tc=10.4 K) at 298 K and 104 K are determined by X-ray analysis. The packing pattern of donors is nearly analogous to κ-(BEDT-TTF)2I3. The counter anion, Cu(NCS)2−, has no positional disorder and constructs a peculiar sheet where a copper ion is coordinated with a sulfur and two nitrogen atoms to form a one-dimensional polymer with a permanent dipole moment.

The single crystal of (HMTTeF)4(PF6)2 was first prepared by the electrochemical method. The X-ray crystal structure analysis revealed that among four HMTTeF molecules in the unit cell, three are stacked to form trimeric molecular column along the a-axis and the remaining one is located between the HMTTeF columns, having very short intermolecular Te–Te distances with the HMTTeF column.

(BEDT-TTF)2IAuBr was synthesized and the crystal structure of this material was determined to be of the β″- type, being isomorphous to β″-(BEDT-TTF)2AuBr2. The polarized reflectance spectrum indicates that the electronic structure of this salt is of considerable two-dimensional character.

The crystal structure of 2,5-bis(dicyanomethylene)-2,5-dihydrothienot [3,2-b]thiophene and bis(ethylenedithio) tetrathiafulvalene complex showed a weak face to face interaction and sheet-like networks with intermolecular N···S and S···S interactions, and the shortest S···S contact is 3.48 A between the acceptors.

Several charge transfer complexes of HMTTeF (hexamethylenetetratellurafulvalene) with TCNQs, p-quinones, and other π-acceptors were prepared and electrical resistivities were measured with compaction samples. Some of them revealed very low resistivities (ρRT

The electronic spectra and structure of the single crystals of azacycl[3.3.3]azine derivatives have been investigated by the reflection and absorption measurements. In addition to the π-π* transitions of in-plane polarization, the out of plane polarized transition have been found which are due to the intermolecular charge transfer transition between the stacked molecules of the same species.

The two-dimensional strucrture of α-(BEDT-TTF)3(ReO4)2 on the (010) plane is very similar to that of (BEDT-TTF)3(ClO4)2, although the three dimensional structure is quite different from each other. The slight geometrical difference between the crystallographically independent molecules suggests the different formal charge of these molecules.

The conductivity of BF3, H2SO4, and ClSO3H doped polyacetylene films is measured as a function of dopant concentration and temperature. The conductivity at 295 K of the heavily doped film is σ295K= 220 Ω−1cm−1 for BF3, 130 Ω−1cm−1 for H2SO4, and 245 Ω−1cm−1 for ClSO3H, respectively. The conductivity of ClSO3H doped film is metallic between 295 and 250 K.

The crystal structures of methylthio and ethanedithio substituted peri-condensed Weitz type donors, bis(methylthio)dithiapyrene and bis(ethanedithio)dithiapyrene, showed sheet-like networks of dimeric pairs of the donor molecules.

An ambient pressure superconductivity of (BEDT-TTF)2Cu(SCN)2 was observed by d.c. magnetic susceptibility and electrical conductivity measurements. The superconducting critical temperature is the highest (TC=10.4 K) among the organic superconductors so far obtained, even though the anion has a positional disorder in the crystal.

The title complex which is isostructural to e-(BEDT-TTF)2I3 (I8)0.5 changes its conducting property from semiconductive to metallic by tempering with the loss of its weight. This metallic state retains down to 0.5 K and this product is regarded as being different from α- and β-(BEDT-TTF)2IBr2.

Sigle crystals of a metallic (phthalocyaninato)nickel hexafluoro antimonate, (NiPc)2SbF6, were newly prepared by the use of an electrochemical technique. NiPc is stacked one-dimensionally in a slight zigzag way, which quite resembles the structure of highly conducting NiPcI.

Hexacyanobutadiene (HCBD) gives dark red single crystals with equimolar perylene. The crystal structure analysis shows that the complex has mixed regular stacks. The physical properties of the single crystals indicate that the complex is an insulator with neutral ground state and close to neutral-ionic boundary.

Three new diterpenes, which possess a cyclononane skeleton, have been isolated from the brown alga Pachydictyon coriaceum, and their structures have been determined spectroscopically.

Optical reflection and dc conductivity measurements of (DBTTF)8–(SnCl6)3 single crystals were carried out. The temperature dependence of the conductivity behaves as (A/T3) exp(−Eg/2kT) in the temperature range above 85 K. The obtained activation energy Δ = 1010 K is fairly comparable with the result estimated by the optical study.