Structural Systematics of Rare Earth Complexes. XXII 4‐Methylpyridinium Salts of Diverse Complex Aqua/Chloro/Lanthanoid(III) Species

Abstract

Abstract4‐Methylpyridinium cations, mpyH+, crystallized with complex aqua/chloro/lanthanoid(III) species for the gamut of the rare earth series, have ‘domains of existence’ defined for the following forms: The triclinic $P{\bar 1}$ series (mpyH)2[{(H2O)3Cl3Ln(μ‐Cl)(2|2)}2], previously defined for the Ln = La–Nd members (those for La, Pr characterized by full structure determinations); The triclinic $P{\bar 1}$ series (mpyH)2[(H2O)3LnCl4]Cl, previously defined for the Ln = Eu, Ho members by full structure determinations, is here augmented by the Ln = Nd, Sm examples (full structure determinations, the latter a new ‘light’ Ln extremum); A new monoclinic C2/c series (mpyH)2[(H2O)4LnCl3]Cl2, defined for the Ln = Er–Yb extrema (full structural characterizations for the Ln = Er, Tm, Yb members); the lanthanoid‐containing entity (which, with the cations, exhibits some disorder) is a neutral molecule of a new type. For the Ln = Lu case, a fully ordered derivative monoclinic C2 form has been obtained in a cell one half the size. Other types have also been characterized, thus: For Ln = La, (mpyH)8[{(H2O)3Cl3La(μ‐Cl)(2|2)}2]‐[{(H2O)4Cl2La(μ‐Cl)2La(OH2)2Cl2(μ‐Cl)(2|2)}2]Cl4·6H2O·mpy has been defined by a full structural determination; the binuclear anion is similar to that in (a), albeit with some disorder, with the tetranuclear anion derivative of it. For Ln = Lu, (mpyH)2[(H2O)5LuCl2]Cl3 is defined by a full structure determination. For Ln = Y, (mpyH)2[(H2O)7YCl]Cl4 is defined by a full structure determination; here, and in (ii), the complex component is cationic.