A net of intermolecular contacts in organic crystals contains a finite number of strong contacts sufficient for the net formation. These contacts constitute a subnet referred to as the critical net. Critical nets of 1754 crystalline hydrocarbons in six most common structural classes (supergiants) are studied. Coordination numbers and the critical net topology are analyzed, the predominant topological types (dia, pcu, hex, bnn, etc.) are revealed. The critical net is found to be quite economical in 95% cases and containing n + Δ (Δ = 0-2) symmetrically independent contacts, where n is their minimal possible number.

中文翻译：

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分子晶体的 ZORKII 结构类和关键拓扑

有机晶体中的分子间接触网包含有限数量的足以形成网状结构的强接触。这些联系构成了称为关键网络的子网。研究了 6 种最常见的结构类别（超巨星）中 1754 种结晶碳氢化合物的临界网。分析了坐标数和关键网络拓扑，揭示了主要的拓扑类型（dia、pcu、hex、bnn 等）。发现临界网络在 95% 的情况下非常经济，并且包含 n + Δ (Δ = 0-2) 个对称独立的接触，其中 n 是它们的最小可能数量。