title: Guest-driven luminescence: lanthanide-based host-guest systems with bimodal emissive properties based on a guest-driven approach.
abstract: A series of discrete closed, semi-closed, and polymeric lanthanide-based [{Ln(H(2)O)(8)}(3+)subsetLn(III)(2)L(4)] host-guest systems with tetragonal prism-like structure have been designed and synthesized through the ligand-dominated approach. These nanoscopic cages are robust and can be maintained upon guest exchange. Within the restricting space, the luminescence intensity of the encapsulated [Ln(H(2)O)(8)](3+) species is dramatically enhanced due to the vibrational movements originating from the O-H oscillators in the coordinated water molecules being effectively reduced by the host-guest H-bonding interactions. Based on the guest-driven approach, tunable emission and bimodal emission (UV/Vis/NIR) of these [{Ln(H(2)O)(8)}(3+)subsetLn(III)(2)L(4)] supramolecular systems are successfully realized. Moreover, the strong luminescence originating from [{Ln(H(2)O)(8)}(3+)subsetLn(III)(2)L(4)] host-guest system can be quenched by encapsulation of d-block metal quenchers, such as Fe(3+) and Cu(2+), through solid-state f-d metal exchange. Additionally, this study demonstrates that the photoinduced solid-state guest-independent emission spectrum could be one of the most diagnostic techniques for monitoring the solid-state guest-exchange process.
authors.affiliation: College of Chemistry, Chemical Engineering and Materials Science, Key Lab of Molecular and Nano Probe, Engineering Research Center of Pesticide and Medicine, Intermediate Clean Production, Ministry of Education, Shandong Normal University, Jinan, 250014, PR China.
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Ma
authors.forename: Yu-Bin
authors.initials: YB
authors.lastname: Dong