Atoms are combined into molecules by covalent bonding, which involves the sharing of electrons. Two or more molecules will associate with each other by noncovalent interactions. These are weaker attractive forces, such as the coulombic attraction between partial charges. Nitrous oxide is a gas that has various uses, including as an anaesthetic and as a component of rocket fuel. In the gas phase, these molecules can come together in a variety of dimeric forms, as described by East and coworkers. Pasukaro76 made a LEGO version of the nonpolar N-in dimer (which happens to be the high energy conformation on the potential energy surface described by East).