title: Influence of para substituents in controlling photophysical behavior and different non-covalent weak interactions in zinc complexes of a phenol based "end-off" compartmental ligand.
abstract: Three dinuclear zinc(II) complexes with "end-off" compartmental ligands, namely 2,6-bis(N-ethylmorpholine-iminomethyl)-4-R-phenol (R = -CH3, Cl, (t)Bu) have been synthesized with the aim of exploring the role of the para substituent present in the ligand backbone in controlling the structural diversity, photophysical properties and different weak interactions of the complexes. All three species, with the general formula {2[Zn2L(CH3COO)2][Zn(NCS)4]}, show the complex anion Zn(NCS)4(2-) as a common structural feature decisive for crystallization. Interestingly, all of them possess several non-covalent weak interactions where the nature of the "R" group plays an essential role as exposed by DFT study. Besides exhibiting fluorescence behavior, the complexes also show para substitution controlled phosphorescence both at room and low temperature. Anisotropy studies suggest the existence of complexes 2 and 3 as dimers in solution. The origins of the unusual room temperature phosphorescence and fluorescence behavior of the complexes have been rationalized in the light of theoretical calculations.
authors.affiliation: Department of Chemistry, University of Calcutta, 92 A. P. C. Road, Kolkata 700 009, India. dasdebasis2001@yahoo.com.
authors.forename: Prateeti
authors.initials: P
authors.lastname: Chakraborty
authors.affiliation: Department of Chemistry, University of Calcutta, 92 A. P. C. Road, Kolkata 700 009, India. dasdebasis2001@yahoo.com.
authors.forename: Jaydeep
authors.initials: J
authors.lastname: Adhikary
authors.affiliation: Department of Chemistry, Presidency University, Kolkata 700073, India. pchemsg@gmail.com.
authors.forename: Sugata
authors.initials: S
authors.lastname: Samanta
authors.affiliation: Department of Chemistry, University of Calcutta, 92 A. P. C. Road, Kolkata 700 009, India. dasdebasis2001@yahoo.com.
authors.forename: Ishani
authors.initials: I
authors.lastname: Majumder
authors.affiliation: Dipartimento di Chimica, University of Parma, Viale delle Scienze 17/A, 43124 Parma, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Massera
authors.affiliation: Chimie Et Interdisciplinarité, Synthèse, Analyse, Modélisation (CEISAM), UMR CNRS no. 6320, BP 92208, Université de Nantes, 2, Rue de la Houssinière, 44322 Nantes, Cedex 3, France. daniel.escudero@univ-nantes.fr.
authors.forename: Daniel
authors.initials: D
authors.lastname: Escudero
authors.affiliation: Department of Chemistry, Presidency University, Kolkata 700073, India. pchemsg@gmail.com.
authors.forename: Sanjib
authors.initials: S
authors.lastname: Ghosh
authors.affiliation: Departament de Química, Universitat de les Illes Balears, Crta. de Valldemossa km 7.5, 07122 Palma, Baleares, Spain. toni.frontera@uib.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Bauza
authors.affiliation: Departament de Química, Universitat de les Illes Balears, Crta. de Valldemossa km 7.5, 07122 Palma, Baleares, Spain. toni.frontera@uib.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Frontera
authors.affiliation: Department of Chemistry, University of Calcutta, 92 A. P. C. Road, Kolkata 700 009, India. dasdebasis2001@yahoo.com.
authors.forename: Debasis
authors.initials: D
authors.lastname: Das