The molecules they were touching were perfectly flat, and must have been pretty well adhered to the silver surface. Now that I think about it, silver is used as

The molecules they were touching were perfectly flat, and must have been pretty well adhered to the silver surface. Now that I think about it, silver is used as a catalyst, and they had to heat it to 90C to cause the reaction. So it sounds like it was more of a problem of overcoming the inherent stability of the molecule to get it to do anything at all.