Extraction and theoretical study on the complexation of the strontium cation with beauvericin

• Published in: Journal of radioanalytical and nuclear chemistry Vol. 295; no. 2; pp. 1119 - 1122
• Main Authors: Makrlík, E., Toman, P., Vaňura, P.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.02.2013; Springer
• Subjects: Cationic; Chemistry; Chemistry and Materials Science; Complexation; Constants; Diagnostic Radiology; Extraction; Hadrons; Heavy Ions; Inorganic Chemistry; Mathematical analysis; Nitrobenzenes; Nuclear Chemistry; Nuclear Physics; Physical Chemistry; Strontium; Water–nitrobenzene system; Complexation; Complex structure; Beauvericin; Strontium cation; DFT calculations; Extraction and stability constants
• ISSN: 0236-5731; 1588-2780
• DOI: 10.1007/s10967-012-1886-8

From extraction experiments and γ -activity measurements, the extraction constant corresponding to the equilibrium Sr 2+ (aq) + 2A − (aq) + 1 (nb) ⇔ 1 ·Sr 2+ (nb) + 2A − (nb) taking place in the two-phase water–nitrobenzene system (A −  = picrate, 1  = beauvericin; aq = aqueous phase, nb = nitrobenzene phase) was evaluated as log  K ex ( 1 ·Sr 2+ ,2A − ) = −0.6 ± 0.1. Further, the stability constant of the 1 ·Sr 2+ complex in nitrobenzene saturated with water was calculated for a temperature of 25 °C: log  β nb ( 1 ·Sr 2+ ) = 8.5 ± 0.1. Finally, by using quantum-mechanical DFT calculations, the most probable structure of the resulting cationic complex 1 ·Sr 2+ was derived.