Four phosphorescent dinuclear Pd–Pd complexes were synthesized by using the clamping ligand N,N′-diphenylformamidine and primary ligands of C∧N, which both have high field strength to enhance luminescence complexes. The single-crystal data confirmed their clamshell structures revealed distances between 2.829 2.864 Å. In addition, time-dependent density functional theory calculations nature metal–metal-to-ligand charge transfer ligand-to-ligand in these Moreover, 3 4 used fabricate an OLED a...

Rapid nanoscale imaging of the bulk heterojunction layer in organic solar cells is essential to continued development high-performance devices. Unfortunately, commonly used techniques such as tunneling electron microscopy (TEM) and atomic force (AFM) suffer from significant drawbacks. For instance, assuming domain identity phase contrast or topographical features can lead inaccurate morphological conclusions. Here we demonstrate a technique known photo-induced (PiFM) for cell heterojunctions...

Nine C2 symmetric diols have been examined as additives in the l-proline-catalyzed direct aldol reaction with significant improvement enantioselectivity, conversion efficiency, and yield. Loading of 1 mol % (S)-BINOL leads to desired products up 98% ee 90% A transition state is proposed.

We present a general strategy of reparametrizing semiempirical (SE) methods against ab initio (AI) for combined quantum mechanical and molecular (QM/MM) simulations specific chemical reactions in condensed phases. The resulting approach, designated Reaction Path Force Matching (RP-FM), features cycles sampling configurations along reaction path on an efficient SE/MM potential energy surface (PES) adjusting parameters (SRPs) the SE method such that atomic forces computed at target AI/MM level...

Cyanamide (NH2CN) and its isomer, carbodiimide (HNCNH), may form adenine in the interstellar medium (ISM) via a series of reactions. Therefore, they are considered key prebiotic molecules study origin life. We used three-phase NAUTILUS chemical code, which includes gas, dust surface, icy mantle, to investigate formation destruction cyanamide carbodiimide. added over 200 new reactions two isomers related species, established relatively complete network. applied cold core, hot corino/core...

First-principles determination of free energy profiles for condensed-phase chemical reactions is hampered by the daunting costs associated with configurational sampling on ab initio quantum mechanical/molecular mechanical (AI/MM) potential surfaces. Here, we report a new method that enables efficient AI/MM simulations through mean force fitting. In this method, path in collective variables (CVs) first determined an reactive aiding potential. Based configurations sampled along path,...

Adenosine triphosphate (ATP)-binding cassette (ABC) transporters form a family of molecular motor proteins that couple ATP hydrolysis to substrate translocation across cell membranes. Each nucleotide binding domain ABC-transporters contains highly conserved H-loop histidine residue, whose precise mechanistic role in functions has remained elusive. By using combined quantum mechanical and (QM/MM) calculations, we showed the residue H662 E. coli HlyB, bacterial ABC-transporter, can act first...

A facile synthesis of previously unknown, well-separated, uniform chiral microstructures from achiral π-conjugated organic molecules was developed by simple solution process. Detailed characterization and formation mechanism were presented. By structure modification or temperature change, the pitch can be fine tuned. Our result opens new possibilities for novel materials in which chirality is coupled to device performance.

As a future lighting source, high power LED is significant in that it provides decades of lifetime under normal operation, requiring fraction the demanded for traditional solutions. For to be viable there are many technical challenges resolved. Among them light extraction efficiency, chip overheating, and output degradation key issues, which turn out all related packaging materials. This talk outlines those reports some recent progresses resolving problems

Abstract C 2 ‐Chiral 1,1,4,4‐tetraaryl‐ or 1,1,4,4‐tetraalkyl‐substituted butanetetraols have been conveniently synthesized via arylation alkylation of unprotected diethyl (2 R ,3 )‐ and S )‐tartrates with Grignard reagent. The chiral 1,1,4,4‐tetrasubstituted were characterized by IR, 1 H‐ 13 C‐NMR, as well LC/MS.

Abstract Hydroxyacetone (CH 3 COCH 2 OH) is one of the smallest molecules that contain both hydroxyl and carbonyl group on neighboring carbon atoms. This steric configuration characteristic saccharides determines their biochemical activity. The attempt to search for hydroxyacetone toward massive star formation region Sagittarius B2(N) was unsuccessful. Here we report first detection CH OH in solar-type protostar IRAS 16293–2422 B, using Atacama Large Millimeter Array science verification...

Abstract A straightforward synthetic strategy to an anionic gemini surfactant having both N ‐acylamide and carboxylate groups in a molecule has been demonstrated. The surface properties of the surfactant, such as CMC (critical micelle concentration), C 20 (the concentration required reduce tension solvent by mN / m), γ at CMC), ∏ pressure Γ max maximum excess air/aqueous solution interface), min minimum area per air/water CMC/C ratio (a measure tendency form micelles relative adsorbtion have...

HlyB functions as an adenosine triphosphate (ATP)-binding cassette (ABC) transporter that enables bacteria to secrete toxins at the expense of ATP hydrolysis. Our previous work, based on potential energy profiles from combined quantum mechanical and molecular (QM/MM) calculations, has suggested highly conserved H-loop His residue H662 in nucleotide binding domain (NBD) E. coli may catalyze hydrolysis through proton relay. To further test this hypothesis when entropic contributions are taken...

Abstract Substituted toluenyl groups are considered as close isosteres of the thymine residue. They can be recognized by DNA polymerases if they were thymine. These toluene derivatives generally inert toward radical additions, including [2+2] photo‐cycloadditions, due to stable structure aromatic ring and usually used solvents for reactions. Surprisingly, after incorporating into dinucleotide framework, we found that UV excited residue readily dimerizes with moiety through a photo‐addition...

The cyclobutane pyrimidine dimer (CPD) is a major photoproduct of deoxyribonucleic acid (DNA) that damaged by ultraviolet light. This DNA lesion can be repaired photolyase with the aid UV light and two cofactors. To understand repair mechanism CPD whether protonation participates in process, cycloreversion reactions four models proton transfers between adjacent residue Glu283 were explored through quantum mechanical method. Two-dimensional maps potential energy surface vacuum implicit water...

DNA photolyase targets the primary ultraviolet (UV)-induced lesion─cyclobutane pyrimidine dimer (CPD), attaches to it, and catalyzes its dissociation. The catalytic mechanism of role conserved residue E283 remain subjects debate. This study employs two-dimensional potential energy surface maps minimum free paths calculated at ωB97XD/6-31G/MM level elucidate these mechanisms. Results suggest that process follows a sequential, stepwise reaction in which C5-C5 C6-C6 bonds are cleaved order,...

ABSTRACT Aminoacetonitrile (AAN), also known as glycinenitrile, has been suggested a possible precursor of glycine and adenine in the interstellar medium. Here, we present chemical modelling AAN its isomers hot cores using three-phase model NAUTILUS with addition over 300 reactions three related species. Our models predicted peak gas-phase abundance reaching order 10$^{-8}$, which is consistent observation towards Sgr B2(N). Regarding reaction pathways isomers, found that primarily formed...

Aminoacetonitrile (AAN), also known as glycinenitrile, has been suggested a possible precursor of glycine and adenine in the interstellar medium. Here we present chemical modeling AAN its isomers hot cores using three-phase model NAUTILUS with addition over 300 reactions three related species. Our models predicted peak gas phase abundance reaching order 10-8, which is consistent observation towards Sgr B2(N). Regarding reaction pathways isomers, found that primarily formed via free radical...