Cu₂ is the chemical name for copper, which is "Cuivre" in French. It's also the small cocktail lounge attached to Cuivre french restaurant. It's a quirkily appointed space with two rows of movie theater-like seats facing each other and denim covered blocks that double as tables and chairs. Cocktails are mostly original variations on classics like the gin sour and the Manhattan. To eat, there is a menu of burgers on homemade buns topped with gourmet ingredients, like truffle mayo, Roquefort and raclette cheese and onion jam. They're ironically presented wrapped in wax paper and served in a cardboard box. Order one. They're good.