Fig. 5From: Specific energy contributions from competing hydrogen-bonded structures in six polymorphs of phenobarbitalPacking diagram of polymorph X, showing interactions of a selected Pbtl molecule (drawn in ball-and-sticks-style) within the same C-1 chain (blue) and with molecules belonging to three neighbouring chains (@1–@3; see Fig. 4). Together, hydrogen bonding and the …@1 @2 @1 @2… stacking of chain pairs account for 78 % of E T,Cry Back to article page