Carbon atom social behavior

Recent work with carbon suggests that for small (nano-sized) particles: (a) diamond instead of graphite is stable at low pressure (making possible the hard diamond-like-carbon coatings on grocery-store bar-code scanners), and (b) that liquid carbon droplets are stable to sublimation i.e. that carbon vapor first condenses as a stable liquid. Regardless, liquid metals in "containerless settings" generally supercool well below the melting temperatures before solidification.

At left is a closeup of carbon's T vs. P phase diagram in a high-temperature low-pressure region, with dashed red the vapor (V) pressure line, and for 2nm particles a solid black liquid (L) to graphite (G) line and a solid blue graphite to diamond (D) line. The dotted lines show how these lines move for larger (3nm) particles instead.