Publications by authors named "Xingchu Zhang"

Manipulation of laser-assisted field evaporation taking place at a sub-picosecond time scale relies on a full understanding of the dynamics at a microscopic level. We use first-principles methods to investigate the mechanism of energy absorption and charge draining during fast evaporation of silicon in a high electrostatic field with ultrafast-laser illumination. The results show that laser energy absorption to trigger field evaporation can be described by an effective cross section, which depends on the photon frequency and the static field strength.

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A density functional investigation of the interaction between calcium and magnesium univalent cations and RNA pyrimidine base (cytosine, thymine and uracil) was performed to determine geometric coordinates and free energies for all possible stable isomers at B3LYP/6-311 + G (2df, 2p) level. The most stable isomers C1M, T1M and U1M (M = Ca+ and Mg+) with the lowest free energy among the same pyrimidine base tautomers were calculated to determine the characters of infrared vibrations. According to the results, two characteristic infrared vibrations at wave numbers 1,684 and 1,765 cm(-1) were found for single pyrimidine base C1, at 1,747 and 1,792 cm(-1) for T1, 1,763 and at 1,796 cm(-1) for U1.

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