A three-dimensional tin(II) phosphonatobenzenesulfonate with Sn₄O₁₂ clusters

The hydrothermal reaction of SnCl₂·2H₂O with 4-phosphonobenzenesulfonic acid (H₃L) and sodium hydroxide has yielded the title compound, poly[μ-hydroxido-μ₇-(4-phosphonatobenzenesulfonato)-ditin(II)], [Sn₂(C₆H₄O₆PS)(OH)]_n. The inorganic building unit is an Sn₄O₁₂ cluster which is composed of edge-sharing SnO₄ and SnO₅ polyhedra. The clusters are interconnected via P and S atoms from the organic acid to form layers in the ab plane. These layers are linked to each other through pillaring benzene groups parallel to the c axis to form a three-dimensional structure.