The elements rhodium (Rh, blue) and iridium (Ir, green) are chemically similar metals. But in these surprising molecules, incorporating Rh instead of Ir results in a change in the configuration of the (yellow) sulfur rectangles. Specifically, the compounds are [{Rh2( η5-C5Me5)2(µ-CH2)2}2(µ-S4)]2+(left), and [{Ir2(η5-C5Me5)2(µ-CH2)2}2(µ-S4)]2+(right).