title: Spin-flip reactions of Zr + C2H6 researched by relativistic density functional theory.
abstract: Density functional theory (DFT) with relativistic corrections of zero-order regular approximation (ZORA) has been applied to explore the reaction mechanisms of ethane dehydrogenation by Zr atom with triplet and singlet spin-states. Among the complicated minimum energy reaction path, the available states involves three transition states (TS), and four stationary states (1) to (4) and one intersystem crossing with spin-flip (marked by -->): (3) Zr + C 2 H 6 → (3) Zr-CH 3 -CH 3 ((3)1) → (3)TS 1/2 → (3) ZrH-CH 2 -CH 3 ((3)2) → (3) TS 2/3 --> (1) ZrH2-CH2 = CH2 ((1) 3) → (1) TS 3/4 → (1) ZrH 3 -CH = CH 2 ((1)4). The minimum energy crossing point is determined with the help of the DFT fractional-occupation-number (FON) approach. The spin inversion leads the reaction pathway transferring from the triplet potential energy surface (PES) to the singlet's accompanying with the activation of the second C-H bond. The overall reaction is calculated to be exothermic by about 231 kJ mol(-1). Frequency and NBO analysis are also applied to confirm with the experimental observed data.
authors.affiliation: School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 200240, Shanghai, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xiao
authors.forename: Xian-Yang
authors.initials: XY
authors.lastname: Chen
authors.forename: Yi-Xiang
authors.initials: YX
authors.lastname: Qiu
authors.forename: Shu-Guang
authors.initials: SG
authors.lastname: Wang