| Autor: |
Khatun E; Department of Chemistry, DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE) , Indian Institute of Technology Madras , Chennai 600036 , India., Bodiuzzaman M; Department of Chemistry, DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE) , Indian Institute of Technology Madras , Chennai 600036 , India., Sugi KS; Department of Chemistry, DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE) , Indian Institute of Technology Madras , Chennai 600036 , India., Chakraborty P; Department of Chemistry, DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE) , Indian Institute of Technology Madras , Chennai 600036 , India., Paramasivam G; Department of Chemistry, DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE) , Indian Institute of Technology Madras , Chennai 600036 , India., Dar WA; Department of Chemistry, DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE) , Indian Institute of Technology Madras , Chennai 600036 , India., Ahuja T; Department of Chemistry, DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE) , Indian Institute of Technology Madras , Chennai 600036 , India., Antharjanam S; Sophisticated Analytical Instruments Facility , Indian Institute of Technology Madras , Chennai 600036 , India., Pradeep T; Department of Chemistry, DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE) , Indian Institute of Technology Madras , Chennai 600036 , India. |
| Abstrakt: |
We introduce a cluster coprotected by thiol and diphosphine ligands, [Ag 22 (dppe) 4 (2,5-DMBT) 12 Cl 4 ] 2+ (dppe = 1,2-bis(diphenylphosphino)ethane; 2,5-DMBT= 2,5-dimethylbenzenethiol), which has an Ag 10 core encapsulated by an Ag 12 (dppe) 4 (2,5-DMBT) 12 Cl 4 shell. The Ag 10 core comprises two Ag 5 distorted trigonal bipyramidal units and is uncommon in Au and Ag nanoclusters. The electrospray ionization mass spectrum reveals that the cluster is divalent and contains four free electrons. An uncommon crystallization-induced enhancement of emission is observed in the cluster. The emission is weak in the solution and amorphous states. However, it is enhanced 12 times in the crystalline state compared to the amorphous state. A detailed investigation of the crystal structure suggests that well-arranged C-H···π and π···π interactions between the ligands are the major factors for this enhanced emission. Further, in-depth structural elucidation and density functional theory calculations suggest that the cluster is a superatom with four magic electrons. |
