Computational study of cesium cation interactions with neutral and anionic compounds related to soil organic matter.
The gas-phase cesium cation affinities (CsCAs) and basicities (CsCBs) for 56 simple neutral compounds (mostly aromatic molecules) and 41 anions (carboxylates and phenolates) were calculated using density functional theory (DFT), in the context of the interaction of Cs(+) with soil organic matter (SOM). The B3LYP/def2-TZVP method gives in general CsCAs and CsCBs in a good agreement with experimental data. The strong deviations in case of NO(3)(-) and CsSO(4)(-) anions need further experimental investigations as the high-level CCSD(T) calculations support B3LYP results. Different cesium cation complexation patterns between Cs(+) and the neutral and anionic systems are discussed. As expected, the strongest CsCAs are observed for anions. The corresponding quantities are approximately by 4-5 times higher than for the neutral counterparts, being in the range 90-118 kcal/mol. The weakest cesium cation bonding is observed in the case of unsubstituted aromatic systems (11-15 kcal/mol).
Burk
Peeter
P
Institute of Chemistry, Chair of Chemical Physics, University of Tartu, Jakobi 2, 51014 Tartu, Estonia. burk@ut.ee
Tammiku-Taul
Jaana
J
Tamp
Sven
S
Sikk
Lauri
L
Sillar
Kaido
K
Mayeux
Charly
C
Gal
Jean-François
JF
Maria
Pierre-Charles
PC
D001673:Biodegradation, Environmental; D002264:Carboxylic Acids / Q000737:chemistry; D002412:Cations / Q000737:chemistry; D002586:Cesium / Q000737:chemistry*; D006812:Humic Substances / Q000032:analysis*; D006841:Hydrocarbons, Aromatic / Q000737:chemistry; D062385:Hydroxybenzoates / Q000737:chemistry; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D044367:Phase Transition; D012989:Soil Pollutants / Q000737:chemistry*
D002264:Carboxylic Acids; D002412:Cations; D006812:Humic Substances; D006841:Hydrocarbons, Aromatic; D062385:Hydroxybenzoates; D012989:Soil Pollutants; D002586:Cesium