Supplementary Material for Structural and bonding properties of Ta2Cn−/0 (n = 1−7) clusters: Size-selected anion photoelectron spectroscopy and theoretical calculations

FIG. S1. Low-lying isomers of Ta2Cn− (n = 1−7) clusters optimized at the PBE/aug-cc-pVTZ/C/aug-cc-pVTZ-pp/Ta level. The energies in parentheses are calculated at the CCSD(T)/aug-cc-pVTZ/C/aug-cc-pVTZ-pp/Ta level with zero-point energy correction. Cyan and red balls represent the tantalum and carbon atoms, respectively.

FIG. S2. Low-lying isomers of neutral Ta2C4 cluster. The relative energy is calculated at the PBE/aug-cc-pVTZ/C/aug-cc-pVTZ-pp/Ta level. The energies in parentheses are calculated at the CCSD(T)/aug-cc-pVTZ/C/aug-cc-pVTZ-pp/Ta level with zero-point energy correction. Cyan and red balls represent the tantalum and carbon atoms, respectively.

TABLE SI. The calculated theoretical VDE/ADE values of Ta2C1-4− clusters using PBE/B3LYP/TPSS functionals and corresponding experimental data. The energy in parentheses is the deviation defined by equation |Etheoretical - Eexperimental|. The average deviation of four clusters is also computed.

TABLE SII. Cartesian coordinates of low-lying isomers of Ta2Cn− (n = 1−7) clusters.

TABLE SIII. Cartesian coordinates of low-lying isomers of neutral Ta2Cn (n = 1−7) clusters.

图S1：Ta2Cn− (n = 1−7) 簇的低位异构体，已在PBE/aug-cc-pVTZ/C/aug-cc-pVTZ-pp/Ta水平进行优化。括号中的能量值采用CCSD(T)/aug-cc-pVTZ/C/aug-cc-pVTZ-pp/Ta水平计算，并进行了零点能量校正。蓝色和红色球分别代表钽和碳原子。图S2：中性Ta2C4簇的低位异构体。相对能量在PBE/aug-cc-pVTZ/C/aug-cc-pVTZ-pp/Ta水平计算得出。括号中的能量值采用CCSD(T)/aug-cc-pVTZ/C/aug-cc-pVTZ-pp/Ta水平计算，并进行了零点能量校正。蓝色和红色球分别代表钽和碳原子。表SI：使用PBE/B3LYP/TPSS泛函计算得到的Ta2C1-4−簇的理论VDE/ADE值及其对应的实验数据。括号中的能量为方程|E理论 - E实验|定义的偏差。四个簇的平均偏差也进行了计算。表SII：Ta2Cn− (n = 1−7) 簇低位异构体的笛卡尔坐标。表SIII：中性Ta2Cn (n = 1−7) 簇低位异构体的笛卡尔坐标。