TY - JOUR
T1 - Complexation thermodynamics of UO22+/diglycolamide complex in a room temperature ionic liquid
T2 - A study by optical spectroscopy and microcalorimetry
AU - Ansari, Seraj A.
AU - Dumpala, Rama Mohana R.
AU - Verboom, Willem
AU - Mohapatra, Prasanta K.
N1 - Funding Information:
Authors thank Dr. S. Kannan, Director, Radiochemistry and Isotope Group, BARC for his support and encouragement.
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2022/7/1
Y1 - 2022/7/1
N2 - Complexation thermodynamics of UO22+ and a series of N,N,N’,N’-tetraalkyl diglycolamide (TRDGA) ligands having alkyl chains –CH3 to –C6H13 were investigated in an ionic liquid (IL). The complexation constant for UO22+/DGA complex increased linearly with increasing alkyl chain length of DGA from tetramethyl (logβ1 = 4.52, logβ2 = 8.01) to tetrahexyl (logβ1 = 5.62, logβ2 = 10.3). There were two types of species recorded in the calorimetric titration for all the four ligands, one having endothermic complexation, and other exothermic. This observation was in contrast with those observed for aqueous medium, where both the stepwise complexation enthalpies were endothermic. The structural feature indicated the formation of [UO2L2]2+ type of complex without water or Tf2N− anion in the primary coordination sphere of the uranyl cation.
AB - Complexation thermodynamics of UO22+ and a series of N,N,N’,N’-tetraalkyl diglycolamide (TRDGA) ligands having alkyl chains –CH3 to –C6H13 were investigated in an ionic liquid (IL). The complexation constant for UO22+/DGA complex increased linearly with increasing alkyl chain length of DGA from tetramethyl (logβ1 = 4.52, logβ2 = 8.01) to tetrahexyl (logβ1 = 5.62, logβ2 = 10.3). There were two types of species recorded in the calorimetric titration for all the four ligands, one having endothermic complexation, and other exothermic. This observation was in contrast with those observed for aqueous medium, where both the stepwise complexation enthalpies were endothermic. The structural feature indicated the formation of [UO2L2]2+ type of complex without water or Tf2N− anion in the primary coordination sphere of the uranyl cation.
KW - Actinides
KW - Calorimetry
KW - Complexation
KW - Diglycolamide
KW - Ionic liquid
KW - 2023 OA procedure
UR - http://www.scopus.com/inward/record.url?scp=85127830835&partnerID=8YFLogxK
U2 - 10.1016/j.poly.2022.115820
DO - 10.1016/j.poly.2022.115820
M3 - Article
AN - SCOPUS:85127830835
VL - 220
JO - Polyhedron
JF - Polyhedron
SN - 0277-5387
M1 - 115820
ER -