Organocatalytic Ring-Opening Polymerization of -Caprolactone Using (-('-butylimidazolium)alkane Dicationic Ionic Liquids as the Metal-Free Catalysts: Polymer Synthesis, Kinetics and DFT Mechanistic Study.

In this work, we successfully synthesized high thermal stable 1,n-(-('-butylimidazolium)alkane hexafluorophosphates (1,n-[Bim][PF], n = 4, 6, 8, and 10) catalysts in 55-70% yields from imidazole which were applied as non-toxic DILs catalysts with 1-butanol as initiator for the bulk ROP of -caprolactone (CL) in the varied ratio of CL/BuOH/1,4-[Bim][PF] from 200/1.0/0.25-4.

Solvent Dependence of Double Proton Transfer in the Formic Acid-Formamidine Complex: Path Integral Molecular Dynamics Investigation.

Solvent dependence of double proton transfer in the formic acid-formamidine (FA-FN) complex at room temperature was investigated by means of ab initio path integral molecular dynamics (AIPIMD) simulation with taking nuclear quantum and thermal effects into account. The conductor-like screening model (COSMO) was applied for solvent effect. In comparison with gas phase, double proton delocalization between two heavy atoms (O and N) in FA-FN were observed with reduced proton transfer barrier height in low dielectric constant medium (<4.

TD-DFT Study of Absorption and Emission Spectra of 2-(2'-Aminophenyl)benzothiazole Derivatives in Water.

Reduction of aromatic azides to amines is an important property of hydrogen sulphide (HS) which is useful in fluorescence microscopy and HS probing in cells. The aim of this work is to study the substituent effect on the absorption and emission spectra of 2-(2'-aminophenyl)benzothiazole (APBT) in order to design APBT derivatives for the use of HS detection. Absorption and emission spectra of APBT derivatives in aqueous environment were calculated using density functional theory (DFT) and time-dependent DFT (TD-DFT) at B3LYP/6-311+G(d,p) level.

Molecular simulations of ultra-low-energy nitrogen ion bombardment of A-DNA in vacuum.

For investigating mechanisms involved in low-energy ion beam induced mutation, besides experiments using low-energy and low-fluence ions to bombard naked DNA, molecular simulations were carried out as an effort towards the insight in molecular interactions between ions and DNA. In the current study, Monte Carlo (MC) and molecular dynamics (MD) simulations were applied. The results of MC simulations provide some clues about the interaction energies and sites of preference of N-ion bombardment on an A-DNA short duplex strand.