title: Halogen Bonding and Chalcogen Bonding in 4,7-Dibromo-5,6-dinitro-2,1,3-benzothiadiazole.
abstract: An organic solid, 4,7-dibromo-5,6-dinitro-2,1,3-benzothiadiazole, has been designed to serve as an illustrative example to quantitatively evaluate the relative merits of halogen and chalcogen bonding in terms of charge density features. The compound displays two polymorphic modifications, one crystallizing in a non-centrosymmetric space group (Z' = 1) and the other in a centrosymmetric space group with two molecules in the asymmetric unit (Z' = 2). Topological analysis based on QTAIM clearly brings out the dominance of the chalcogen bond over the halogen bond along with an indication that halogen bonds are more directional compared to chalcogen bonds. The cohesive energies calculated with the absence of both strong and weak hydrogen bonds as well as stacking interaction are indicative of the stabilities associated with the polymorphic forms.
authors.affiliation: Solid State and Structural Chemistry Unit, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Mysore S
authors.initials: MS
authors.lastname: Pavan
authors.affiliation: Solid State and Structural Chemistry Unit, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Ajay Kumar
authors.initials: AK
authors.lastname: Jana
authors.affiliation: Solid State and Structural Chemistry Unit, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: S
authors.initials: S
authors.lastname: Natarajan
authors.affiliation: Solid State and Structural Chemistry Unit, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Tayur N
authors.initials: TN
authors.lastname: Guru Row
mesh_terms: D018011:Chalcogens / Q000737:chemistry*; D003198:Computer Simulation; D003461:Crystallography; D006219:Halogens / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D013830:Thiadiazoles / Q000737:chemistry*
chemical_list: D018011:Chalcogens; D006219:Halogens; D013830:Thiadiazoles; C015700:benzo-1,2,3-thiadiazole