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A facile room-temperature synthetic method is presented to produce alkali metal salts of tert-butyl phosphonic acid. The reaction between equimolar amounts of alkali metal carbonates and tert-butyl phosphonic acid in methanol results in the formation of [(tBuPO3H)Li(H2O)3•(H2O)] (1), [(tBuPO3)Na2(H2O)4]n (2), and [(tBuPO3H)K(H2O)]n (3). Solid-state structures of these compounds have been confirmed by single-crystal X-ray diffraction studies and further validated using numerous spectroscopic and analytical techniques. Compounds 1--3 are polymeric solids that are predominantly made up of a 1-D polymeric metal phosphonate chain. This synthetic approach leads to the formation of network structures/polymers in the solid state that otherwise are absent in solution due to the ionic nature of the interaction between the alkali metal ions and phosphonate anions. Apart from the multidentate nature of the phosphonate ligands, additional hydrogen bonding interactions involving water molecules, free P--OH groups, and P O moieties allow these chains to be propagated into 2-D sheets. We have further utilized the completely metalated sodium phosphonate 2 to synthesize layered metal phosphonates [(tBuPO3)Ca(H2O)]n (4), [(tBuPO3)Mn(H2O)]n (5) and [(tBuPO3)Co(H2O)]n (6) via a simple metathesis reaction. [ABSTRACT FROM AUTHOR]

New organophosphate complexes [Ln(dippH)3(dippH2)3]·(H2O)6, (Ln = Dy, Yb and Y; dippH2 = 2,6-diisopropylphenyl phosphate), displaying octahedral coordination geometry around the metal ion, exhibit unusual slow relaxation of magnetisation, which is investigated through experimental studies and ab initio CASSCF calculations. [ABSTRACT FROM AUTHOR]

Single-ion magnets (SIMs) have attracted wide attention in recent years. Despite tremendous progress in late lanthanide SIMs, reports on early lanthanides exhibiting SIM characteristics are scarce. A series of five novel 18-crown-6 encapsulated mononuclear early lanthanide(III) organophosphates, [{(18-crown-6)Ln(dippH)3}{(18-crown-6)Ln(dippH)2(dippH2)}]·[I3] [Ln = Ce (1), Pr (2), Nd (3)] and [{Ln(18-crown-6)(dippH)2(H2O)}·{I3}] [Ln = Sm (4) and Eu (5)], have been synthesised in the present study. 18-crown-6 coordinates to Ln(III) ions in an equatorial position while the axial positions are occupied by either three phosphate moieties as in 1–3 or two phosphate moieties and one water molecule as in 4 and 5, resulting in a muffin-shaped coordination geometry around the Ln(III) centres. Magnetic susceptibility measurements reveal that Ce and Nd complexes are field-induced single-ion magnets with significant barrier heights. Furthermore, the ab initio CASSCF/RASSI-SO/SINGLE_ANISO calculations on complexes 1 and 3 reveal significant QTM in the ground state rationalising the field-induced single-ion magnetism behaviour of these complexes. [ABSTRACT FROM AUTHOR]