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Measurement of Rh2-stretching frequencies from complexes of known metal-metal separations, along with literature data, enable the derivation of Herschbach and Laurie type (H-L) relations for Rh2 systems. Raman spectroscopic measurements enable the determination of Rh2 force constants. Rh2-stretching frequency facilitates the determination of metal-metal separations and the uncertainty is for -0.05 angstroms.

The synthesis of conjugated rigid rod and nonconjugated flexible polymers and corresponding model compounds bearing the d(super 9)-d(super 9) M(sub 2)(dppm)(sub 2)(super 2+) fragments (where dppm=bis(diphenylphosphino)methane) is reported. The presence of pi-delocalization between the M(sub 2)(dppm)(sub 2) fragments is addressed using the comparison between aryl- and alkyl-diisocyanide assembling ligands.

Syntheses and characterization of the Pd2-bonded organometallic polymers of the type{[Pd2-(dmb)(sub 2)(diphos)](ClO4)(sub 2)} with diphos = dppb, dpppen, dpph, and dpa is discussed. The strategy to use metallic fragments that are only functionalizable at the axial positions in order to synthesize polymeric or oligomeric materials is presented.

The mixed-ligand polymers {[M(diphos)(CN-t-Bu)2]BF4}n (M = Cu, Ag; diphos = dppm, dppb, dpppen, dpph) and {[M(diphos)(dmb)]BF4}n(dmb = 1,8-diisocyano-p-menthane) are synthesized and characterized. TGA, DSC, XRD, and solid-state luminescence spectra and emission lifetimes are reported.

The tile bridging ligand has become an increasingly versatile building block over the past thirty years. A new strategy to synthesize organometallic oligomers is presented, which consists of using the title disocyanide and chelated metal fragments with bis(diphenylphosphine)alkanes.

As a function of temperature, pressure, solvents, substrate and cluster concentrations, and counterions, the catalytic properties of the title cluster toward the homogeneous hydrogenation of phenylacetylene, diphenylethyne and phenyl-1-propyne are investigated.

Research has been conducted on (Pd (sub)3 (super)2+) cluster. The authors demonstrate that this cluster exhibits affinity for Br (super)- ions to produce stable Pd (sub)3 (Br) (super)+ adduct.

The stoichiometric and catalytic activations of alkyl halides and acid chlorides by the unsaturated Pd3(dppm)(sub 3)(CO)(super 2+) cluster (Pd(sub 3)(super 2+)) are investigated in detail. The regeneration of the Pd(sub 3)(super 2+) catalyst from the Pd(sub 3)(X)(super +) species is presented.

The Pd(sub 4)(dppm)(sub 4)(H)(sub 2)(super 2+) can be prepared in four different manner this cluster is an electrocatalyst for H(sub 2) evolution from H(super +) and HCO(sub 2) decomposition. The key intermediate is found to be Pd(sub 4)(dppm)(sub 4)(H)(sub 3)(super +).

The {[M-(dmb)(sub 2)]TCNQ.xTCNQ degrees}(sub n) materials (M = Cu,Ag; x=0.05, 1.0, 1.5) are prepared from the ionic polymers {[M(dmb)(sub 2)]Y}(sub n) (Y= BF(sub 4)-(super -), ClO(sub 4), where for x = 0 and 0.5 the materials are insulating, the x = 1.0 and 1.5 show electric conductivity associated with semi-conductors. The {[Ag(dmb)(sub 2)]- TCNQ.1.5TCNQ}(sub n) crystal exhibits an unprecedented multilayer carpet structure where crossed TCNQ(super 5/2-) chains are observed.

Two tetracarboxylatetetrabenzoporphyrinzinc(ii), TCPBP (9,18,27,36-tetrakis-meso-(4-carboxyphenyl)tetrabenzoporphyrinatozinc(ii)) and TCPEBP (9,18,27,36-tetra-(4-carboxyphenylethynyl)tetrabenzoporphyrinatozinc(ii)), and their two corresponding porphyrins, TCPP (tetrakis-meso-(4-carboxyphenyl)porphyrinatozinc(ii)) and TCPEP (5,10,15,20-tetra-(4-carboxyphenylethynyl)porphyrinatozinc(ii)) as sodium salts in a 1 : 1 mixture of 2MeTHF/MeOH at 77 K exhibit phosphorescence in the near-IR region with maxima ranging from 785 to 1005 nm. The position of these triplet state emissions has been corroborated from DFT (B3LYP) by calculating the total energy difference between the ground, S0, and lowest energy triplet excited state T1 (the calculated position ranges from 797 to 1041 nm). At both temperatures, 77 and 298 K, these dyes make ionic driven host–guest assemblies with the unsaturated redox-active cluster Pd3(dppm)3(CO)2+ ([Pd32+], dppm = Ph2PCH2PPh2 as a PF6− salt). The formation of these assemblies is accompanied by a quenching of the phosphorescence band, without changing the emission lifetime. This phenomenon is consistent with the formation of the non-emissive assemblies dye…[Pd32+]x according to dye + [Pd32+] → dye…[Pd32+]x (x = 1–4), where only the porphyrin and tetrabenzoporphyrin dyes are phosphorescent. Quenching analysis confirmed that a static quenching mechanism operates. In one case, the quenching rate (kQ) has been evaluated from transient absorption spectroscopy (TAS) where the signal associated with the dye's triplet state exhibits a very short lifetime τ(T1), thus corroborating the efficient quenching. The quenching rate (1/τ(T1)) is much faster (3.0 × 108 s−1) than that expected for the other dye…[Pd32+]x assemblies in the literature (∼104 s−1) known for their triplet–triplet energy transfer. Based on the excited state driving force argumentation for oxidative quenching, this fast process is assigned to a predominant photo-induced electron transfer (3dye* + [Pd32+] → dye+Ṗ + [Pd3+Ṗ]). [ABSTRACT FROM AUTHOR]