中文摘要：

NCCS^＋，CNCS^＋和CCNS^＋是[N，C，C，S]^＋体系中的三个动力学和热力学上稳定性较高的异构体，在精确的实验条件下是可以观察到的．其中，NCCS^＋是热力学上最稳定的异构体，其次是异构体CNCO^＋和CCNO^＋，能量分别比NCCS^＋高12．98kcal·mol^-1和77．34kcal·mol^-1．利用计算得到的键长，键特征和正电荷密度分布，本研究揭示了这三个异构体的结构本质．

英文摘要：

The structural nature of NCCS^＋ , CNCS ^＋ and CCNS ^＋ was investigated, which are three stable linear isomers of the [ N,C,C,S] ＋ system and should be kinetically stable and experimentally observed provided that accurately experimental conditions are available. The linear isomer NCCS ^＋ is ther- modynamically the most stable species followed by CNCO ^＋ and CCNO ^＋ at 12. 98 kcal . mol ^- 1 and 77.34 kcal . mol^-1, respectively. Their structural nature is discussed based on the computed bond lengths, bonding characteristics, and positive charge distribution.