Probing structure, thermochemistry, electron affinity, and magnetic moment of thulium-doped silicon clusters TmSi n (n = 3-10) and their anions with density functional theory.

The most stable structures and electronic properties of TmSi n (n = 3-10) clusters and their anions have been probed by using the ABCluster global search technique combined with the PBE, TPSSh, and B3LYP density functional methods. The results revealed that the most stable structures of neutral TmSi n and their anions can be regarded as substituting a Si atom of the ground state structure of Si n + 1 with a Tm atom. The reliable AEAs, VDEs and simulated PES of TmSi n (n = 3-10) are presented. Calculations of HOMO-LUMO gap revealed that introducing Tm atom to Si cluster can improve photochemical reactivity of the cluster. The NPA analyses indicated that the 4f electron of Tm atom in TmSi n (n = 3-10) and their anions do not participate in bonding. The total magnetic moments of TmSi n are mainly provided by the 4f electrons of Tm atom. The dissociation energy of Tm atom from the most stable structure of TmSi n and their anions has been calculated to examine relative stability.