Clustering augmentation

The molecular structure of the closo 12-vertex 1-SBnHn cluster (17) has been studied by electron diffraction methods augmented by ab initio calculations. Substantial distortions away from the regular icosahedron occurred by expansion of the pentagonal belt adjacent to sulfur.73 The UV-PES spectra of 17 has also been reported,71 and its microwave spectrum has been investigated and demonstrated that the molecule had C5v symmetry.74... 

The Cauchy moments are derived and implemented for the approximate triples model CC3 with the proper N scaling (where N denotes the number of basis functions). The Cauchy moments are calculated for the Ne, Ar, and Kr atoms using the hierarchy of the coupled-cluster models CCS, CC2, CCSD, CC3 and a large correlation-consistent basis sets augmented with diffuse functions. A detailed investigation of the one- and A-electron errors shows that the CC3 results have the accuracy comparable to the experimental results. 

Dunning s correlation consistent basis sets cc-pVAZ [27] augmented with diffuse functions [28] were used in the calculations. We considered cardinal numbers X—D, T, Q, 5, 6 and single (s), double (d), triple (t), and quadruple (q) augmentations. The orbitals were not allowed to relax in the coupled cluster response calculations. 

The photodimerization reaction of anthracene in supercritical CO2 was studied systematically at different CO2 densities. Unlike in normal liqnid solvents, the reaction in supercritical CO2 is significant even at anthracene concentrations as low as a few micromolar. At comparable anthracene concentrations, the photodimerization reaction is one order of magnitude more efficient in CO2 than in normal liqnid solvents. The results also show that the efficient photodimerization reaction of anthracene is hardly affected by the local density augmentation (or solute-solvent clustering) in supercritical CO2 (Bunker et al., 1997). 

Furthermore, it was indicated that miR-17-19b cluster included in miR-17-92 cluster inhibited apoptotic cell death, and accelerated c-Myc-induced lymphomagenesis in mice reconstituted with miR-17-19b cluster-over-expressed haematopoietic stem cells (43). In addition, the miR-17-92 cluster has been reported to augment angiogenesis in vivo by down-regulation of anti-angiogenic thrombospondin-1 and coimective tissue growth factor in Ras-transformed colonoc Tes (45). 

Dews M, Homayouni A, Yu D et al. Augmentation of tumor angiogenesis by a Myc-activated mi-croRNA cluster. YatGeuet 2006 38 1060-1065. 

Steady-state fluorescence spectroscopy has also been used to study solvation processes in supercritical fluids. For example, Okada et al. (29) and Kajimoto and co-workers (30) studied intramolecular excited-state complexation (exciplex) and charge-transfer formation, respectively, in supercritical CHF3. In the latter studies, the observed spectral shift was more than expected based on the McRae theory (56,57), this was attributed to cluster formation. In other studies, Brennecke and Eckert (5,31,44,45) examined the fluorescence of pyrene in supercritical CO2, C2HSteady-state emission spectra were used to show density augmentation near the critical point. Additional studies investigated the formation of the pyrene excimer (i.e., the reaction of excited- and ground-state pyrene monomers to form the excited-state dimer). These authors concluded that the observance of the pyrene excimer in the supercritical fluid medium was a consequence of increased solute-solute interactions. 

Influence of Solvent-solute Clustering on Reactions Due to Augmentation in Local Polarity... 

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