A helical chain of [Co(1,10-phen)2(V2O4)(O3PCH2CH2CH2PO3)]n (1) and a stepped chain of [{Co(1,10-phen)2}2(V4O10)(O3PCH2CH2CH2CH2PO3)(2H2O)]n (2) have been synthesized under hydrothermal conditions using [Co(1,10-phen)2]2+ as the metal-organic subunit and organic diphosphonate
![Graphical abstract: Hydrothermal synthesis and crystal structure of two hetero-transition metal polymers: [Co(1,10-phen)2(V2O4) (O3PCH2CH2CH2PO3)]n and [{Co(1,10-phen)2}2(V4O10) (O3PCH2CH2CH2CH2PO3)(2H2O)]n](http://hg.y866.cn/compound/lib/scimg/usr/1/B209564E.jpg)
