Theoretical Investigation of LaC^n and La_2C^n(n=-1,0,+1)Clusters

用密度泛函方法研究了ＬａＣｎ及Ｌａ２Ｃｎ（ｎ＝－１，０，＋１）分子簇的结构和稳定性．对Ｌａ２Ｃｎ体系，提出了两种可能构型，其中一种具有Ｃ２ｖ对称性，另一种具有Ｄ∞ｈ对称性．计算结果表明，对Ｌａ２Ｃｎ，当ｎ＝＋１，－１时，线状结构最稳定，并且在ｎ＝＋１时，Ｃ２ｖ结构极不稳定有收敛向线状结构的趋势．而当ｎ＝０时，Ｃ２ｖ结构最稳定．最后还计算了ＬａＣ和Ｌａ２Ｃ分子簇的电子亲和势和离化能．

LaCn and La2Cn ( n = -1, 0, +1 ) clusters have been studied using density functional method. For La2C cluster, two isomers have been considered,which have C2v and D∞h symmetry respectively. The main conclusion of this investigation is that in La2Cn, at n = +1, -1, linear isomer is the ground state, and at n = +1, no stable structure was located for C2v symmetry isomer, where as at n = 0, isomer with C2v symmetry is the most stable. Finally, the electron affinity and ionization potential of LaC and La2C clusters were also reported.