A d-Methionine-Bonded Nanosized Heteropolyoxotungstate with Photocoloration

A d-methionine-bonded nanosized arsenotungstate, Ba₉K₁₀H₆[{As₂W₁₉O₆₇(H₂O)}₂{AsW₉O₃₃}₂{W₃O₆(H₂O)(d-Met)}₂{W₂O₄(OH)(d-Met)}]·60H₂O [1; d-Met = d-methionine (C₅H₁₁NO₂S)], is constructed without the use of lanthanide ions. The polyanion of 1 contains two {As₂W₁₉O₆₇(H₂O)}^14- building blocks and two {B-β-AsW₉O₃₃}^9- subunits, integrated together with a {W₂O₄(OH)(d-Met)}²⁺ and two {W₃O₆(H₂O)(d-Met)}⁵⁺ subclusters. Interestingly, 1 displays a highly reversible photocoloration property with a half-life (t_1/2) time measured as about 0.793 min.