С учетом рассчитанной нами ранее величины b-фактора аквакомплекса иона магния при различных концентрациях магниевых солей рассчитан однократный коэффициент экстракционного разделения изотопов (a) изотопной пары для 24Mg–26Mg для экстракционной системы, содержащей в органической фазе комплексы катиона магния с краун-эфирами. Более высокий заряд катиона магния по сравнению с литием и тем самым более прочные связи магний – кислород в кольце макроцикла может объяснить причину отсутствия влияния молекул воды в координационной сфере. Квантово-химические расчеты частот колебаний изотопных форм комплекса с краун-эфиром проводили с помощью программы Firefly. Для расчета всех комплексов применялся базис RHF/6-311++G**. Показано, что наиболее эффективным макроциклическим лигандом для практического разделения изотопов магния является бензо-15-краун-5.

The effect of structures of the derivatives of [2-(diphenylphosphorylmethoxy)phenyl]-diphenylphosphine oxide (L 1 ) on the complexation properties toward rare-earth elements (REE) was studied. A new structural analogue of L 1 , isopropyl 2-(diphenylphosphorylmethoxy)benzoate (L 3 ), was synthesized. The extraction of REE by the carboxylated podand L 3 in a 1,1,7-trihydrododecafluoroheptanol—water system with the HNO 3 concentration varied in a range from 1 to 6 mol L −1 was studied. The stability constants of the neodymium(iii) and erbium(iii) nitrate complexes with L 3 and 1-(methoxydiphenylphosphoryl)-2-diphenylphosphoryl-4-ethylbenzene (L 2 ) and of lutetium(iii) nitrate and chloride complexes with L 2 in 1,1,7-trihydrododecafluorheptanol were determined. The properties of the membranes of the ion-selective electrodes based on L 1 , L 2 , and L 3 toward REE cations were tested. The crystal structures of L 3 and [NdL 3 (NO 3 ) 3 (DMSO) 2 ] were determined by X-ray diffraction analysis.

Data on the extraction of lithium salts and the distribution of extractant in the LiX–H 2 O- benzo-15-crown-5–CHCl 3 systems, where X – is Br – , ClO_4^ - , and SCN – , have been first obtained in wide ranges of salt and extractant concentrations. The solubility of benzo-15-crown-5-ether in water in the temperature range 25–60°C and the isotherm of the distribution of crown ether between chloroform and water at room temperature have been determined.

Data on the extraction of lithium salts and the distribution of extractant in the LiX–H2O- benzo-15-crown-5–CHCl3 systems, where X– is Br–, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\text{ClO}}_{4}^{ - },$$\end{document} and SCN–, have been first obtained in wide ranges of salt and extractant concentrations. The solubility of benzo-15-crown-5-ether in water in the temperature range 25–60°C and the isotherm of the distribution of crown ether between chloroform and water at room temperature have been determined.

Extraction of rare earth elements (REE) in 1,1,7-trihydrododecafluoroheptanol–water system with phosphoryl podands derived from diphosphonic acids of general formula 2-[(HO)(EtO)(O)P]-4-Et–C 6 H 3 –(OCH 2 CH 2 ) n –OC 6 H 3 -4-Et-2-[P(O)(OEt)(OH)], n = 1–5 has been studied. Effect of medium acidity on REE extraction efficiency and selectivity has been studied. Crystal structure of 1,5-bis[2-(oxyethoxyphosphoryl)phenoxy]-3-oxapentane has been established by X-ray diffraction.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Extraction of rare earth elements with bis(diphenylphosphorylmethyl) ethers of oligoethylene glycols Ph2P(O)CH2O(CH2CH2O)nCH2P(O)Ph2 (Ln, n = 0–5) in 1,1,7-trihydrododecafluoroheptanol–water system with variable HNO3 concentration from 0.5 to 6 mol/L has been studied Complexes of Nd, Eu, Lu, and Er nitrates with L0 and L2 have been obtained. Crystal structures of [Ln2 (NO3)6] · xH2O (Ln = Nd, x = 1.99; Ln = Eu, x = 1; Ln = Er, x = 6.5; Ln = Lu, x = 6), and [LnL(NO3)3(H2O)] (Ln = Nd, Er) have been studied by X-ray diffraction, IR spectroscopy, and thermogravimetry. Correlation between X-ray diffraction and extraction data has been revealed.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Chloroform–water extraction systems have been studied using crown-ethers as extracting agents, namely: benzo-15-crown-5 (B15C5), 2,3-naphtho-15-crown-5 (N15C5), 4′-nitro-benzo-15-crown-5 (NO 2 B15C5), 4′- tert -butyl-benzo-15-crown-5 (TBB15C5), and 4′-acetyl-benzo-15-crown-5 (AcB15C5). Extraction isotherms of these systems have been obtained, and an attempt made to elucidate the effect of the structure of extracting agent on extraction characteristics. IR-spectroscopic studies have been performed for selected crown-ethers and their complexes in crystalline form and in chloroform solutions, namely, for N15C5, NO 2 B15C5, AcB15C5, and B15C5. The complexes LiN15C5H 2 OClO 4 ( 1 ), LiN15C5H 2 OI ( 2 ), LiNO 2 B15C5H 2 OI ( 3 ), LiAcB15C5H 2 OI ( 4 ), and LiTBB15C5H 2 OI ( 5 ) have been isolated for the first time and characterized by IR spectroscopy. Single-crystal X-ray data have been obtained for complexes 1–3 .

Extraction of rare earth elements with bis (diphenylphosphorylmethyl) ethers of oligoethylene glycols Ph 2 P(O)CH 2 O(CH 2 CH 2 O) n CH 2 P(O)Ph 2 (L n , n = 0–5) in 1,1,7-trihydrododecafluoroheptanol–water system with variable HNO 3 concentration from 0.5 to 6 mol/L has been studied Complexes of Nd, Eu, Lu, and Er nitrates with L 0 and L 2 have been obtained. Crystal structures of [Ln 2 L 3 0 (NO 3 ) 6 ] · x H 2 O (Ln = Nd, x = 1.99; Ln = Eu, x = 1; Ln = Er, x = 6.5; Ln = Lu, x = 6) and [LnL 2 (NO 3 ) 3 (H 2 O)] (Ln = Nd, Er) have been studied by X-ray diffraction, IR spectroscopy, and thermogravimetry. Correlation between X-ray diffraction and extraction data has been revealed.

The extraction of tetrafluoroboric acid from aqueous solutions to a solution of benzo-15-crown-5 (B15С5, 1 mol L-1) in chloroform is shown to occur due to complexation with the ratio of components HBF4: B15С5 = 1: 1.5. It was revealed by IR spectroscopy that the whole crown ether in the extract is coordinated. The 1: 1 HBF4•В15С5 complex was isolated and characterized using IR spectroscopy and X-ray diffraction analysis. The O(2) and O(4) atoms of the crown ether ring participate in the coordination.

The complex formation of lithium thiocyanate with benzo-15-crown-5 (B15C5) was studied. The possibility of formation of both anhydrous and crystal water-containing complexes was demonstrated. The complexes LiB15C5NCS and LiB15C5H 2 ONCS were synthesized and characterized by X-ray diffraction and IR spectroscopy.