Charge transfer complexes of picolines with sigma- and pi-acceptors
Humaira Razzaq1, Rumana Qureshi, Naveed Kausar Janjua
1Chemistry Department, Quaid-i-Azam University, 45320 Islamabad, Pakistan. hunza_pk2@yahoo.com
Abstract:
In the present study CT complexes of 2-, 3- and 4-Picolines with (DDQ) 2, 3-dichloro-5, 6-dicyano parabenzoquinone (pi-acceptor) and (I2) Iodine (sigma-acceptor) have been investigated spectrophotometrically in three different solvents (CCl4, CHCl3 and CH2Cl2) at six different temperatures. The formation constants of the CT complexes were determined by the Benesi-Hildebrand equation. The thermodynamic parameters were calculated by Van(')t Hoff equation. The DeltaH degrees , DeltaG degrees and DeltaS degrees values are all negative implying that the formation of studied complexes is exothermic in nature.
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