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The synthesis and characterization of redox-active, tetrathiafulvalene (TTF)-phosphine and ferrocene (FC)-phosphine complexes based on a hexanuclear rhenium chalcogenide cluster core that delivers three-dimensional pi-donor hybrid molecules. Cyclic voltammetry experiments demonstrate that these compounds can be reversely oxidized at rather low potentials allowing an easy access to the corresponding radical species.

A face-capped octahedral cluster with 25 metal-based valence electrons- specifically, [Re4Os2Se 8(CN)6](super 3-) is capable to participate in magnetic exchange coupling. The observed ferromagnetic coupling with appended Cu(super II) centers is weak as a result of the cluster spin being diluted over its sizeable core.

The ability of I...I van der Waals interactions to direct the self-assembly of slabs of the radical cation of ethylenedithio-1,2-dilodo-tetrathiafulvalene, EDT-TTF-I2, and polymeric lead iodide covalent anionic layers is demonstrated by the synthesis of single crystals of beta-(EDT-TTF-I2)(sub 2)(super .+)[(Pb(sub 5/6)square(sub 1/6)I2)(super 1/3)](sub 3). A complementary, commensurate pattern of association is revealed at the organic-inorganic interface.

Research has been conducted on the hexanuclear rhenium chalcohalide clusters. The solution chemistry of these clusters has been investigated in the effort to explore the redox chemistry of the electron-rich mineral molecular forms and their substitutional patterns.

A novel method of synthesizing related cage molecules and macrocyclophanes was developed through the use of the same technique for synthesizing TTF vinylogues. The design utilized bis(1,4-dithiafulvenes) as primary substrates. The intermediate underwent the same redox behavior as with 1,4-diathiafulvenes.

Tetrabutylammonium salts of the chalcogen-enriched heterosubstituted, hexanuclear molecular cluster dianions were yielded at room temperature in a reaction of (n-Bu4N)(Re6Q5Cl3(Cl6)) (Q = S, Se) with ((CH3)3Si)2E, (where E = O, S, Se, Te) reagents. Heterosubstituted hexanuclear molecular cluster dianions have been characterized with liquid secondary negative ion mass spectrometry and crystallographic data is presented. A decrease in thermalized average Re-Cl overlap clusters with increased cluster charge is discussed.

The syntheses and structural characterization of the octahedral Re6 cluster anions (Re6S5Cl9) and (Rb+)5(Re6S6Cl8(super 2-))(Re6S7Cl7(super -3)) as well as the molecular (Re6S4Cl10) and the neutral linear-chain polymer (Re6S5Cl8) are discussed. The synthesis is based on the preparation of salts, Rbn(Re6S(sub 4+n)Cl(sub 10-n)), where n = 1-3. The reductive-oxidative and crystallograpic properties of the complexes are discussed.

The results of an analysis of fully oxidized and moderately coupled dimers is reported. The synthesis of thiocyanato-functionalized cluster halide as a tetrabutylammonium salt is also reported. The molecular structure of ((Mes)4TTF)2(MoCl8(NCS)6) includes discrete organic dications interspersed between functionalized cluster dianions in a Cs-Cl type structure. There were smaller coordinating MoNC angles for the isothiocyanate ligands and the Mo6Cl8 cluster core than those of the tetrabutylammonium salt.

A study was done on the neutral molecular component site along the series of metallic organic-inorganic solvates. The series of single crystals composed of a monoanion which is a hexanuclear chalcohalide rhenium cluster and the neutral guest molecules are dimethylformamide. The compounds possess similar basic structural organization in which conducting organic cation radical slabs are sandwiched by inorganic cluster monoanion layers.

Four new mesitylene-anchored dithia- and tetrathiafulvenyl (DTF and TTF) pi-donors with threefold symmetry are synthesized and characterized by cyclic voltammetric, electrocyrstallization and X-ray methods. The studies show that Ph(DTF)3 oxidizes into an electroactive polymer while its methyl derivative does not. For the TTF derivatives, each redox unit behaves independently and cation radical salts can be grown electrochemically thereon. The empirical results are supported by molecular orbital calculations.

Double-sheet coordination polymer layers interspersed with H2O molecules characterize the two-dimensional Gd2(oxalato)(Cu 1,3-propylenebis oxamato)3(Cu H2O 5).20H2O structure. The oxalato bridges, which connect Gd(III) ions, form a parallel double-sheet honeycomb pattern featuring a puckered ladderlike Gd(Cu pba)-connected arrangement. Additionally, the zero-field magnetic susceptibility results show that the three-dimensional ordering of the compound takes place below 1.3 Kelvin. Low- and high-field magnetization analyses indicate that the magnetic interaction of the structure is relatively weak.

Nickel dithiolene complexes symmetrically appended with hydrogen-bond donor/acceptor functionalities such as imide, amide, or cyano/amide groups are synthesized by a straightforward method of wide applicability starting from one single precursor. Single-crystal X-ray structures reveal the occurrence of one type of ribbon common to all compounds that is based on a recurrent self-complimentary intermolecular hydrogen-bonded ring motif.

We have investigated the infrared spectra of the quarter-filled charge-ordered insulators δ-(EDTTTF- CONMe2)2X (X= AsF6, Br) along all three crystallographic directions in the temperature range from 300 to 10 K. DFT-assisted normal mode analysis of the neutral and ionic EDT-TTF-CONMe2 molecule allows us to assign the experimentally observed intramolecular modes and to obtain relevant information on the charge ordering and intramolecular interactions. From frequencies of chargesensitive vibrations we deduce that the charge-ordered state is already present at room temperature and does not change on cooling, in agreement with previous NMR measurements. The spectra taken along the stacking direction clearly show features of vibrational overtones excited due to the anharmonic electronic molecule potential caused by the large charge disproportionation between the molecular sites. The shift of certain vibrational modes indicates the onset of the structural transition below 200 K. [ABSTRACT FROM AUTHOR]

A series of two dimensional (2D) metals is shown to have one single [beta]-slab layered topology despite successive increases of the cluster anion negative charge. The BDT-TTP salts have provided a series of materials with strongly related but slightly different Fermi surfaces.

A unique hydrogen-bonding network is created between inorganic layers of the hybrid perovskites. Hydrogen bonding can provide a channel for stronger electron coupling between perovskites sheets, contributing to the reduction of band gap.

A perspective on the effort accomplished to direct intermolecular interactions in crystalline molecular conductors based on tetrathiafulvalene derivatives is provided. The focus is on the use of directional, electrostatic, normal and weak hydrogen bonds and halogen bonds.

PdCl2 and PtCl2 complexes of the redox active diphosphine P2 have been synthesized, and the palladium one is structurally characterized. It is found that the single crystal x-ray analysis on the resulting compound showed the formation of a dimeric complex salt, formulated as [(dppen)PdCl](sub 2)(OTf)(sub 2).

The deliberate design of a series of single crystals for conducting two-dimensional radical cation salts of o-bis(amide)-appended ethylenedithiotetrathiafulvalene, beta'-[EDT-TTF-(CONH2)2]2X (X = HSO(sub 4)(super -1), ClO(sub 4)(super -1), ReO(sub 4)(super -1)or AsF(sub 6)(super -1) and of their parent monocomponent solid EDT-TTF-(CONH2)2 is discussed. A recurrent, puckered ribbon constructed out of self-complementary, hydrogen-bonded amide...amide ring motifs is an important design element.