Retrosynthetic planning plays an important role in the field of organic chemistry, which could generate a synthetic route for target product. The is series reactions are started from available molecules. most challenging problem generation large search space candidate reactions. Estimating cost has been proved effectively to prune space, achieve higher accuracy with same iteration. And estimati...

We present data on the coverage and nearest-neighbor dependences of the diffusion of CO on Cu(111) by time-lapsed scanning tunneling microscope (STM) imaging. Most notable is a maximum in diffusivity of CO at a local coverage of one molecule per 20 substrate atoms and a repulsion between CO molecules upon approach closer than three adsites, which in combination with a less pronounced increase i...

Anopheles pulcherrimus Theobald has a wide distribution in western Asia and is a potential vector of malaria in Iran. We have examined the rDNA-ITS2 (internal transcribed spacer 2) region of An. pulcherrimus specimens collected during the two peaks of activity (May-June and October-November) from Sistan and Baluchistan province, southeastern Iran. There were no consistent differences between sp...

Interaction of intense ultrashort (few-cycle) laser pulses with atoms and molecules leads to a highly nonlinear nonperturbative regime of electron dynamics and response. Ionized electrons are shown to be controlled by such pulses and the response is described by simple classical models of under and above barrier ionization followed by recollision with the parent ion or collision with neighborin...

The crystal structure of para-methyl-l-phenylalanine at 230 K resembles that of the para-fluorinated analogue from the literature but is commensurately modulated with seven molecules in the asymmetric unit (Z' = 7). At 100 K, the superstructure loses its modulation, leading to a unit cell with Z' = 1, with clear disorder in the phenyl ring orientations. The methyl-substituent in para-methyl-l-p...

Folding into complex 3D structures, protein molecules are responsible for carrying out nearly all of the essential functions in living cells by properly binding to other molecules with a number of chemical bonds connecting neighboring atoms. Locations of these atoms are called the binding sites. To help biologists identify the functions of unknown proteins and to discover new functions of known...

State-of-the art experimental techniques such as scanning tunneling microscopy have great difficulties in extracting detailed structural information about molecules adsorbed on surfaces. By combining atomic force microscopy and Kelvin probe force microscopy with ab initio calculations, we demonstrate that we can obtain a wealth of detailed structural information about the molecule itself and it...

We report the results of the dynamics of a three dimensional lattice of dipolar molecular rotors where the unit cells consist of a dipolar phenylene ring rotating about an axle stabilized by stationary triphenyl groups. The molecules are synthesized such that the lattice may be customized to elicit novel and useful physical phenomena. Using dielectric spectroscopy and H NMR, we demonstrate rapi...

The appearance of ferromagnetic correlations among π electrons of phenanthrene (C14H10) molecules in the herringbone structure is proven for K doped clusters both by ab initio quantum-chemistry calculations and by the direct solution of the many-body Pariser-Parr-Pople Hamiltonian. Magnetic ground states are predicted for one or three additional electrons per phenanthrene molecule. These result...

First principles molecular dynamics (MD) simulations, of water adsorption on the MgOf100g surface, was performed to determine the molecular structure and chemical nature of the adsorbed water at varying coverage. Dissociative adsorption was stabilized by hydrogen bond donation from neighboring water molecules. The dissociation barrier had a strong dependence on coverage. Spontaneous dissociatio...