The use of [Fe(dithiooxalate)2(NO)]2−as a tecton in crystal engineeringCCDC reference numbers 761432–761434. For crystallographic data in CIF or other electronic format see DOI: 10.1039/c1ce05309d.

A series of crystalline salts based on the complex dianion [Fe(dto)2(NO)]2−(dto = 1,2-dithiooxalate) with hydrogen-bond donor cations have been synthesised. The preparation and structural characterisation of the new crystalline phases [4,4′-H2bipy][Fe(dto)2(NO)]·H2O (1), [3,3′-H2bipy][Fe(dto)2(NO)] (2) and [H2Me4bipyz][Fe(dto)2(NO)]·2H2O (3) (Me4bipyz = 3,3′,5,5'-tetramethyl-4,4′-bipyrazole) are reported, and show that a charge-assisted NHdto synthon is formed in each of compounds 1–3. In compound 1the anion forms a dimer in the solid-state, and variable temperature magnetic susceptibility measurements reveal a weak antiferromagnetic interaction with a best fit superexchange parameter J= –3.18 (2) cm−1, where H= –2JS1S2. [ABSTRACT FROM AUTHOR]