[1,1′-Bis(dicyclo­hexyl­phosphino)cobalto­cenium-κ2 P,P′]chlorido(η5-cyclo­penta­dien­yl)ruthenium(II) hexa­fluorido­phosphate

In the title structure, [CoRu(C5H5)(C17H26P)2Cl]PF6, the RuII atom is bonded to a cyclo­penta­dienyl ring, a Cl atom and two P atoms of the chelating 1,1′-bis­(dicyclo­hexyl­phosphino)cobaltocenium (di-cypc) ligand, leading to a three-legged piano-stool coordination. Part of the PF6 − counter-anion is disordered over two positions, with a site-occupancy ratio of 0.898 (7):0.102 (7). The components are linked by C—H⋯F and C—H⋯Cl hydrogen bonds

Coalescence of Carbon Atoms on Cu (111) Surface: Emergence of a Stable Bridging-Metal Structure Motif

By combining first principles transition state location and molecular dynamics simulation, we unambiguously identify a carbon atom approaching induced bridging metal structure formation on Cu (111) surface, which strongly modify the carbon atom coalescence dynamics. The emergence of this new structural motif turns out to be a result of the subtle balance between Cu-C and Cu-Cu interactions. Based on this picture, a simple theoretical model is proposed, which describes a variety of surface chemistries very well

[1,1′-Bis(diphenyl­phosphan­yl)cobalto­cenium]carbonyl­chloridohydrido(triphenyl­phosphane)ruthenium(II) hexa­fluoridophosphate dichloro­methane disolvate

In the title compound, [CoRu(C17H14P)2ClH(C18H15P)(CO)]PF6·2CH2Cl2, the RuII atom is coordinated by three P atoms from a chelating 1,1′-bis­(diphenyl­phosphan­yl)cobaltocenium ligand and a triphenyl­phosphine ligand, one CO ligand, one Cl atom and one H atom in a distorted octa­hedral geometry. In the cobaltocenium unit, the two cyclo­penta­dienyl rings are almost parallel, making a dihedral angle of 1.2 (3)°. The F atoms of the hexa­fluoridophosphate anion are disordered over two sets of sites, with an occupancy ratio of 0.849 (11):0.151 (11). Intra­molecular C—H⋯Cl hydrogen bonds occur in the complex cation. The complex cations, hexa­fluoridophosphate anions and dichloro­methane solvent mol­ecules are linked by inter­molecular C—H⋯F hydrogen bonds

1,1′-Bis(diisobutyl­phosphino)cobalto­cenium hexa­fluorido­phosphate

In the title compound, [Co(C13H22P)2]PF6, the CoIII atom is sandwiched between two (diisobutyl­phosphino)cyclo­penta­dienenyl ligands. The two diisobutyl­phophine units are trans to each other with respect to the CoIII metal center. The PF6 − anion links the cobaltocenium cations via weak C—H⋯F hydrogen bonds into a chain running along the b axis. The chains are further linked by C—H⋯F hydrogen bonds, forming a layer extending parallel to the (10) plane

Deterministic realization of collective measurements via photonic quantum walks

Collective measurements on identically prepared quantum systems can extract more information than local measurements, thereby enhancing information-processing efficiency. Although this nonclassical phenomenon has been known for two decades, it has remained a challenging task to demonstrate the advantage of collective measurements in experiments. Here we introduce a general recipe for performing deterministic collective measurements on two identically prepared qubits based on quantum walks. Using photonic quantum walks, we realize experimentally an optimized collective measurement with fidelity 0.9946 without post selection. As an application, we achieve the highest tomographic efficiency in qubit state tomography to date. Our work offers an effective recipe for beating the precision limit of local measurements in quantum state tomography and metrology. In addition, our study opens an avenue for harvesting the power of collective measurements in quantum information processing and for exploring the intriguing physics behind this power.Comment: Close to the published versio

The Role of XPG in Processing (CAG)n/(CTG)n DNA Hairpins

BACKGROUND: During DNA replication or repair, disease-associated (CAG)n/(CTG)n expansion can result from formation of hairpin structures in the repeat tract of the newly synthesized or nicked DNA strand. Recent studies identified a nick-directed (CAG)n/(CTG)n hairpin repair (HPR) system that removes (CAG)n/(CTG)n hairpins from human cells via endonucleolytic incisions. Because the process is highly similar to the mechanism by which XPG and XPF endonucleases remove bulky DNA lesions during nucleotide excision repair, we assessed the potential role of XPG in conducting (CAG)n/(CTG)n HPR. RESULTS: To determine if the XPG endonuclease is involved in (CAG)n/(CTG)n hairpin removal, two XPG-deficient cell lines (GM16024 and AG08802) were examined for their ability to process (CAG)n/(CTG)n hairpins in vitro. We demonstrated that the GM16024 cell line processes all hairpin substrates as efficiently as HeLa cells, and that the AG08802 cell line is partially defective in HPR. Analysis of repair intermediates revealed that nuclear extracts from both XPG-deficient lines remove CAG/CTG hairpins via incisions, but the incision products are distinct from those generated in HeLa extracts. We also show that purified recombinant XPG protein greatly stimulates HPR in XPG-deficient extracts by promoting an incision 5\u27 to the hairpin. CONCLUSIONS: Our results strongly suggest that 1) human cells possess multiple pathways to remove (CAG)n/(CTG)n hairpins located in newly synthesized (or nicked) DNA strand; and 2) XPG, although not essential for (CAG)n/(CTG)n hairpin removal, stimulates HPR by facilitating a 5\u27 incision to the hairpin. This study reveals a novel role for XPG in genome-maintenance and implicates XPG in diseases caused by trinucleotide repeat expansion