Abstract: The present application provides a use of a mixture comprising less than 75 vol. % of an organic solvent and more than 25 vol. % of water in a preparation of a fac-isomei of a tris homoleptic metal complex, in the presence or the absence of an added salt, and with the proviso that when an added salt contains at least two oxygen atoms, it is used in an amount such that the molar ratio of the salt to the metal in a metal compound used as starting material is less than 1. The present application also provides a method of preparing a fac-isomer for a tris homoleptic metal complex using the mixture.

Abstract: A polymer composition comprising (a) a polybenzimidazole derived from (a1) at least one bis-(ortho-diamino) aromatic compound and (a2) at least one aromatic carboxylic acid or derivative thereof, each containing at least two acid groups and at least one hydroxyl group in ?-position of a carboxylic group; (b) orthophosphoric acid; and (c) polyphosphoric acids of the formula (I): HO[P(O)(OH)]nH, wherein n is an integer from 2 to 20, wherein the polyphosphoric acids of formula (I) are present in an amount of less than 2 mol %, based upon the sum of moles of orthophosphoric acid (b) and polyphosphoric acids (c), and wherein (b) is present in an amount of 1 to 75 moles per mol of a benzimidazole group formed from (a1) and (a2). A polymer membrane comprising the polymer composition, a preferred process for preparing the membrane, and a fuel cell comprising the membrane.