1. Department of Chemistry, University of California, Davis, California 95616 (USA), Fax: (+1) 530‐752‐8995
2. Department of Geology, University of California, Davis, California 95616 (USA)
3. School of Chemistry, Australian Centre of Excellence for Electromaterials Science and Monash Centre for Synchrotron Science, Monash University, Victoria, 3800 (Australia), Fax: (+61) 3‐9905‐4597
4. Present address: Department of Civil Engineering and Geosciences, University of Notre Dame, Notre Dame (Indiana)