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A series of new organometallic polymers of the type {[M(dmb)2]Y} n (dmb = 1,8-diisocyano-p-menthane; Y = BF4 -, NO3 -, ClO4 -, M = Cu; Y = BF4 -, PF6 -, NO3 -, CH3CO2 -, ClO4 -; M = Ag) are reported. These materials have been characterized from single-crystal X-ray diffraction (for {[Ag(dmb)2]Y} n ; Y = BF4 -, NO3 -, ClO4 -), X-ray powder diffraction (which established the isostructurality between M = Cu and Ag and the relative crystallinity level), differential scanning calorimetry (DSC), solid-state magic spinning angle and solution 13C-NMR, and spin−lattice relaxation time measurements (T 1, 13C-NMR). Three synthesis methods were employed in order to obtain highly crystalline, semicrystalline, and highly amorphous {[Cu(dmb)2]BF4} n polymers. One polymer has been successfully characterized from a light-scattering technique. For the amorphous {[Cu(dmb)2]BF4} n polymer, the molecular weights averaged 160 000. The Ag polymers are found to be rather crystalline and exhibit very low solubility properties. Except for the {[Ag(dmb)2]PF6} n and the highly crystalline {[Cu(dmb)2]BF4} n materials, all polymers exhibit glass transitions in the 37−96 °C (305−340 K) range, even if the materials exhibit a very large crystallinity level. The {[M(dmb)2]Y} n organometallic materials (M = Cu, Ag; Y = BF4 -, PF6 -, NO3 -, CH3CO2 -) are also strongly luminescent in the visible range (400−600 nm) at 77 K, exhibiting polyexponential emission decay traces (either in the solid state or in solutions). By comparison with the emission properties of the non-polymeric [M(CN-t-Bu)4](BF4) compounds (M = Cu, Ag) as a model for a monomeric unit, the first and short-lived component of the emission decay traces (30−90% in relative intensity) is associated with a higher-energy emission localized at one M center within the polymer (“monomer-like emission”). This is also confirmed by time-resolved emission spectroscopy from the comparision with the emission maxima. The other components in the polyexponential decays are associated with lower-energy emissions that are only present in the polymers. This phenomenon is associated with an energy transfer metal-to-metal delocalized along the M chain somewhat similar to the exciton phenomenon known in organic solids. The depolarization of the emission light confirms the phenomenon. From density functional theory calculations, the lowest energy excited states have been assigned as MLCT (metal-to-ligand charge transfer) with the HOMO being the M centered d orbitals, and the LUMO being the π* MO centered on the isocyanide groups. X-ray data for {[Ag(dmb)2]BF4} n :  space group P212121, orthorhombic, a = 9.3273(18) Å, b = 13.685(2) Å, c = 22.124(4) Å, V = 2824.0(9) Å3, Z = 4, D calc = 1.353 g/cm3, R = 0.068, R w = 0.073. {[Ag(dmb)2]NO3·0.70H2O} n :  space group P21 /c, monoclinic, a = 13.1746(14) Å, b = 9.7475(11) Å, c = 23.207(3) Å, β = 105.15(1)°, V = 2876.5(6) Å3, Z = 4, D calc = 1.297 g/cm3, R = 0.051, R w = 0.048. {[Ag(dmb)2]ClO4} n :  space group P212121, orthorhombic, a = 9.282(2) Å, b = 13.772(2)...

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The guest-host chemistry of the Pd3(dppm)3C02+ cluster (dppm = ( ( C~H S )~P ) ~C H~) has been investigated in some detail for a series of inorganic and organic substrates by X-ray crystallography (in two cases), UV-visible (and IR) spectroscopy, and molecular mechanics. The two X-ray crystallography characterized complexes are the [Pd3(dppm)3-CO](PF6)y(CH3)2CO and [Pd3(dppm)3CO](CF3C02)(PF6).2(CH3)2CO, which have been used to obtain model structures of the empty cavity (formed by the six upper dppm-phenyl groups) and filled cavity (by the CF3CO2anion), respectively. The latter was also used as a starting structure for the computations. The binding constants ( K 1 were measured spectroscopically using the Benesi-Hildebrand (B.-H.), Scatchard (Scat), and Scott (Scot) methods for about 20 different substrates. The stoichiometry of the association is found to be 1:l where the K I I values range from 0.07 to 10 000 M-I. The substrate-cluster associations are competitive and reversible for most studied systems. In some cases (nitro, cyano, and diazonium derivatives), very slow thermal reactions have been observed. Further molecular mechanic calculations on the cluster-aromatic associated complexes showed that agostic interactions are possible at the minimum computed energy configuration for the aromatic compounds. Overall, these studies show that the binding strength of a substrate (both organic and inorganic) into the bifunctional cavity (metallic center and hydrophobic section) is found to be related to a combination of parameters. These properties are the substrate charge and ligand strength, and the size and hydrophobic properties of the substrates. Crystal data: [Pd3(dppm)3CO](PF6)2, 173 K, triclinic (PI), a = 13.640(4) A, b = 14.0639(17) A, c = 22.4835(15) A, a = 104.291(7)', 0 = 105.143(17)', y = 99.301(18)', V = 3914.7(13) A3, Z = 2, R = 0.039, R, = 0.037; [Pd3(dppm)3CO](CF3C02)(PF6),293 K,monoclinic(P21),a= 11.0189(10)A,b= 26.6515(19)A,c= 14.4746(14) A, 0 = 99.786(9)', V = 4188.9(6) A3, Z = 2, R = 0.057, R, = 0.053. organic molecules and ions within the cavity of the P d 3 ( d~p m )~-COz+ cluster in a variety of solvents at 298 K. During the course of this work, the X-ray structures of [Pt3(dppm)3CO](X)-(Y).n(CH3)2CO ( x = Y = PF6-, n = 1; x = CF3C02-, Y = PFs-,

The new d 10 -d 10 dimer Cu 2 (dppm) 2 (O 2 CCH 3 ) + (as a BF 4 -salt) has been prepared and characterized by X-ray crystallography and by 1 H and 31 P NMR, vibrational, and electronic spectroscopy. The compound is luminescent at 77 K but not at room temperature. MO calculations and geometry optimizations have been performed using the EHMO and DFT models, respectively. In the solid state the Cu 2 separation is 2.788(1) Å where ν(Cu 2 ) ) 87.7 cm -1 , indicating the presence of weak Cu‚‚‚Cu interactions. The MO calculations predict that the lowest energy excited states are MLCT from Cu to phenylphosphine/acetate. These predictions have been confirmed by electronic spectroscopy via a comparison between Cu 2 (dppm) 2 (O 2 CCH 3 ) + and Cu 2 (dppm) 2 (O 2 CC 6 H 5 ) + . In solutions, both NMR ( 1 H and 31 P) and luminescence spectroscopies (time-resolved spectra and τ e analysis) demonstrate the presence of two metal species in solutions: Cu 2 (dppm) 2 (O 2 CCH 3 ) + and Cu 2 (dppm)(O 2 CCH 3 ) + . The dimer crystallizes in the triclinic space group P1 h with a ) 11.572( 2) Å, b ) 12.552(2) Å, c ) 19.543(3) Å, R ) 85.274(12)°, β ) 82.108(11)°, γ ) 68.950(12)°, and Z ) 2.