Triangular cluster complexes

For trinuclear cluster complexes, open (chain) or closed (cycHc) stmctures are possible. Which cluster depends for the most part on the number of valence electrons, 50 in the former and 48 in the latter. The 48-valence electron complex Os2(CO)22 is observed in the cycHc stmcture (7). The molecule possesses a triangular arrangement of osmium atoms with four terminal CO ligands coordinated in a i j -octahedral array about each osmium atom. The molecule Ru (00) 2 is also cycHc and is isomorphous with the osmium analogue. 

It has been several decades since oxo-centered triruthenium-carboxylate complexes with triangular cluster frameworks of Ru3(p3-0)(p-00CR)6 (R = alkyl or aryl) were first isolated [1,2]. In the early 1970s, the first oxo-centered triruthenium complex was structurally characterized by Cotton through X-ray crystal structural determination [3]. Since then, oxo-centered trinuclear ruthenium-carboxylate cluster complexes with general formula [Ru30(00CR)6(L)2L ]n+ (R = aryl or alkyl, L and... 

Catalytic Activity of Pt4 Clusters towEird the Hydration of Acetonitrile Trinuclear Platinum(II) Cluster Complexes A. Synthesis—Cluster Core Transformation Structures of Triangular Cluster Complexes Mechanism of the Cluster Core Transformation Reaction from Square-Planar to Triangular Type EHMO Study Solution Behavior 195pt NMR Spectra of Pts Clusters IV. Concluding Remarks References... 

C-2b c In the cationic Ag(I) arylacetylide complexes [Ag3(dppm)3L]2+ (111) and [Ag3(dppm)3L2] + (112) the trinuclear silver cluster has triangular pyramidal or bipyramidal geometry, with acetylenic C atoms in apical positions. Interatomic distances, 111 Ag—Ag... 

In two studies we have investigated the transformation of the spiked triangular cluster Ru3Pt(//-H)(//4-CCBu )(CO)9(dppe) into the butterfly cluster Ru3Pt( 4-// -C=CHBu )(CO)9(dppe) (Eq. 1) and the formation of the tri-nuclear cluster complex WCo2(CO)8(//-CC6H4Me-4)Cp, from W(CO)2(C6H4Me-4)Cp and Co2(CO)8 in THE(Eq. 2). 

Synthesis of Pd-alkyne clusters Pt carbonyl clusters Pt carbonyl cluster anions Triangular dppm-bridged Pt clusters Pt isocyanide clusters Polymetallic alkene complexes of Pt Polymetallic alkyne complexes of Pt... 

Cluster complexes that obey Cotton s strict definition such as [ Nb6 Cli8]K4 and [ Mo6 C1h]Cs2 have 16 and 24 electrons, respectively, for bonding interactions within the octahedral niobium and molybdenum clusters. In a VB picture, these electrons are consumed for eight two-electron-three-center (2e-3c) or 12 2e-2c bonds, situated in the eight triangular faces and the 12 edges of the respective octahedra. 

Fig. 2.8. Basic structures of some alkyne cluster complexes, (a) Bonded to a butterfly array of metal atoms bearing to an octahedral M4C2 framework (b) and (c) isomeric forms of interaction with a M 3-cluster triangular face...

Some pentanuclear osmium cluster complexes show structures with edge-bridged tetrahedral geometries (c in Fig. 2.17). These structures have the same number of metal-metal bonds as the square-based pyramid but only triangular faces, so the stabilization of intersticial atoms is not possible there. 

Triangular gold cluster complexes also show emissive properties. Thus, excitation of an acetonitrile solution of [Au3Cl HC(PPh3)2 2] leads to a photoluminescence centered at approximately 537 nm with a lifetime of 11 ps. The excited state redox potential for this [Au3] V[Au3] couple is -1.6V versus SSCE. ... 

The Iron Triad.—Mild protonation of the anion [Fe4(CO)u(/t-CO)(/e3-COMe)] yields [Fe4H(CO)i2(i -COMe)], which in turn reacts with strong acid to generate methane from the iy -COMe liquid X-ray crystal structures are reported for both iron complexes. Methods for the s mthesis of triangular metal-cluster complexes containing iUg-alkylidyne ligands have been reported and structures of this tsrpe have been established by X-ray diffraction methods for... 

A triangular triosmium-platinum cluster complex [Os3Pt(/r-H)(/r4-f/ -C = CPh)(CO)io(PCy3)] (349) has been synthesised by the treatment of the unsaturated [Os3Pt(/r-H)2(CO)io(PCy3)] (348) with [LiC=CPh] followed by protonation. 

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