title: Geometric and chelation influences on the electronic structure and optical properties of tetra(carboxylic acid)phenyleneethynylene dyes.
abstract: A quantum-chemical study on the consequences of geometric modification and chelation on the electronic structure and optical properties of a tetra(carboxylic acid)phenyleneethynylene dye, of interest for chemical sensing applications, is presented. Rotation within the central biphenylene and complexation with divalent metal ions--in particular Cu2+--lead to notable changes in the absorption and emission profiles. Calculations at both the density functional theory (DFT) and Hartree-Fock (HF) levels are used to evaluate geometric potential energy surfaces for rotation within the central biphenylene unit; HF coupled with configuration interaction singles (HF-CIS) is used to investigate the first excited state of the dye. Time-dependent DFT (TDDFT) calculations are employed to assess changes in optical absorption and fluorescence as a function of geometry and chelation.
authors.affiliation: Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA.
authors.forename: Asher
authors.initials: A
authors.lastname: Berlin
authors.forename: Chad
authors.initials: C
authors.lastname: Risko
authors.forename: Mark A
authors.initials: MA
authors.lastname: Ratner
mesh_terms: D000042:Absorption; D000480:Alkynes / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry; D002614:Chelating Agents / Q000737:chemistry*; D003505:Cyclodextrins / Q000737:chemistry; D004583:Electrons; D004987:Ethers / Q000737:chemistry*; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry*; D055095:Optics and Photonics; D010795:Phthalic Acids / Q000737:chemistry*; D011789:Quantum Theory; D012399:Rotation; D013997:Time Factors
chemical_list: D000480:Alkynes; D002264:Carboxylic Acids; D002614:Chelating Agents; D003505:Cyclodextrins; D004987:Ethers; D005456:Fluorescent Dyes; D010795:Phthalic Acids; C436384:phenyleneethynylene