New procedures for the preparation of ['Mo IND.3''S IND.4' ('H IND.2'O) (9)] (4+), ['Mo IND.4''S IND.4' ('H IND.2'O) (12)] (5+) and ['Mo IND.7''S IND.8' ('H IND.2'O) (18)] (8+) and their se analogues: redox and substitution studies on the double cube ['Mo IND.7''S IND.8' ('H IND.2'O) (18)] (8+) - Sokolov, M N; Coichev, Nina; Moya, H D; Hernandez-Molina, R; Borman, C D; Sykes, A G (Journal of the Chemical Society. Dalton Transactions, 1997)