(color online) Structure of the polytetrahedral order. ((a)–(d)) Configurations of the largest twenty polytetrahedral clusters for packing of , 0.618, 0.598, and 0.572. (e) The surface area (circles) and cluster sizes (circles) versus the radius of gyration , is defined as the number of tetrahedra face-adjacent to a polytetrahedral cluster formed by quasi-regular tetrahedra. The inset shows the probability of finding a cluster with size . Only data for is shown. The solid lines mark the slopes of the corresponding scaling behaviors: , and . (f) and versus . The figure is reproduced from [41].