Figure 1 (IMAGE) RIKEN Caption Figure 1: Reversible hydrogen addition and release of heterometallic polyhydride clusters (top). The structure changes of the hydride clusters resemble the up-down movement of the pantagraph of a train (bottom). Credit RIKEN Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.