U.S. and German scientists say they\'ve created a sheet of glass just two atoms thick that has earned a spot in the Guinness Book of World Records. The record-breaking sheet of glass is so thin the individual silicon and oxygen atoms are clearly visible via electron microscopy, a release from Cornell University reported Thursday. The glass was an accidental discovery, Cornell physics Professor David A. Muller said; during an attempt to make graphene, a two-dimensional sheet of carbon atoms, on thin copper foils in a quartz furnace, some \"muck\" was noticed on the graphene. Further analysis showed the \"muck\" to be composed of the elements of everyday glass, silicon and oxygen. The researchers said they believed an air leak had caused the copper to react with the quartz, also made of silicon and oxygen, producing the glass layer on the would-be pure graphene. The picture of individual atoms of glass confirms a longstanding theoretical, but unresolved, representation of the arrangement of atoms in glass, they said. \"This is the work that, when I look back at my career, I will be most proud of,\" Muller said. \"It\'s the first time that anyone has been able to see the arrangement of atoms in a glass.\" The research could also yield practical applications, such as by providing a defect-free, ultra-thin material for use in transistors that could improve the performance of processors in devices such as computers and smartphones, the university release said.