%ACorreia, Bruna [Department of Chemistry and Biochemistry University of North Carolina Wilmington 28403 Wilmington North Carolina USA]%ACorreia, Bruna [Department of Chemistry and Biochemistry; University of North Carolina Wilmington; 28403 Wilmington North Carolina USA]%ABrown, Thomas [Department of Chemistry and Biochemistry University of North Carolina Wilmington 28403 Wilmington North Carolina USA]%ABrown, Thomas [Department of Chemistry and Biochemistry; University of North Carolina Wilmington; 28403 Wilmington North Carolina USA]%AReibenspies, Joseph [Department of Chemistry Texas A&,M University 77843 College Station Texas USA]%AReibenspies, Joseph [Department of Chemistry; Texas A&M University; 77843 College Station Texas USA]%ALee, Hee-Seung [Department of Chemistry and Biochemistry; University of North Carolina Wilmington; 28403 Wilmington North Carolina USA]%ALee, Hee‐Seung [Department of Chemistry and Biochemistry University of North Carolina Wilmington 28403 Wilmington North Carolina USA]%AHancock, Robert [Department of Chemistry and Biochemistry University of North Carolina Wilmington 28403 Wilmington North Carolina USA]%AHancock, Robert [Department of Chemistry and Biochemistry; University of North Carolina Wilmington; 28403 Wilmington North Carolina USA]%BJournal Name: European Journal of Inorganic Chemistry; Journal Volume: 2018; Journal Issue: 33; Related Information: CHORUS Timestamp: 2023-09-17 02:19:28 %D2018%IWiley Blackwell (John Wiley & Sons) %JJournal Name: European Journal of Inorganic Chemistry; Journal Volume: 2018; Journal Issue: 33; Related Information: CHORUS Timestamp: 2023-09-17 02:19:28 %K %MOSTI ID: 10072805 %PMedium: X %TExciplex Formation and Aggregation Induced Emission in Di‐( N ‐benzyl)cyclen and Its Complexes – Selective Fluorescence with Lead(II), and as the Cadmium(II) Complex, with the Chloride Ion %X

DB‐cyclen [1,7‐bis(phenylmethyl)‐1,4,7,10‐tetraazacyclododecane] was investigated in 50 % CH3OH/H2O (v/v) as a fluorescent sensor for heavy metal ions, and as the CdIIcomplex as a sensor for anions. The PbIIcomplex showed a unique strong emission at 447 nm, possibly a charge‐transfer band involving the 6p←6s2transition of PbIIand the benzyl fluorophore. ZnIIuniquely produced a significant emission at 353 nm, suggested to be due to an aggregation induced (AIE) mechanism, possibly involving exciplex formation. The free DB‐cyclen ligand produces a fluorescence band at 354 nm above pH ca. 9, accompanied by the slow formation of an aggregate in suspension as indicated by the presence of light scattering peaks in the absorbance spectra, an AIE effect, due to formation of an intermolecular exciplex in the solid state. The role of M···C π contacts in quenching fluorescence in DB‐cyclen complexes or in AIE effects was investigated in the structures of [Pb(DB‐cyclen)(ClO4)2] (1), [Cu(DB‐cyclen)(ClO4)2] (2), [Ag(DB‐cyclen)(ClO4)] (3), and [Cd(DB‐cyclen)(ClO4)(H2O)]ClO4(4). In1there is an intermolecular π contact between the PbIIand a benzyl group from an adjacent complex individual, which is also the case in3, where very short η2intermolecular Ag···C π contacts are found. A strong band at 336 nm is shown in the CdIIDB‐cyclen complex on titration with Clonly: Br, I, S2O32–, and SCNproduced no AIE/exciplex band in the CdIIDB‐cyclen complex: the exciplex forming species may be a Clbridged dimer [Cd(DB‐cyclen)Cl]22+.

%0Journal Article