In his cramped cubicle at Nanomix, a nanotechnology company in Emeryville, CA, just across the bay from San Francisco, theoretical physicist Seung-Hoon Jhi peers at a computer model of a hydrogen fuel tank, carefully tracking the movement of individual molecules. As he raises the temperature of a simulated sheet of boron and nitrogen atoms from a frigid 50 Kelvin to a slightly less chilly 80 Kelvin, he watches the reaction of a handful of hydrogen molecules dotting its surface. The boron nitride sheet undulates, yet the hydrogen molecules hold fast. It's an encouraging sign in a virtual experiment that may have just saved weeks or months of painstaking experimental testing in Nanomix's effort to develop more efficient hydrogen storage materials for fuel cell cars.

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