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Figure 7
Hirshfeld surfaces for the low-temperature phase I (top) and high-pressure phase II (bottom) polymorphs of cyclopropylamine. Each molecule is shown with the Hirshfeld surface mapped with curvedness (left), shape index (centre) and de (right), which is the distance to the nearest atom centre exterior to the surface [for this series mapped between 1.0 Å (red) and 2.5 Å (blue)]. The labels 1 and 2 correspond to the strong and weak hydrogen-bond interactions, respectively, present in the crystal structures of phase I and phase II. The NH2 group of the cyclopropylamine molecule for both these projections is oriented in the same way for phase I and phase II with the N atom pointing towards the viewer and the H atoms pointing away from the viewer (as can be seen from the sketch of the molecule shown beside the Hirshfeld surfaces). The H7 and H6 atoms of the low-temperature phase I are involved in the formation of a short and a long hydrogen bond, respectively, whereas the H7 atom of the high-pressure phase II is the only H atom that participates in the formation of hydrogen bonding.

Journal logoSTRUCTURAL SCIENCE
CRYSTAL ENGINEERING
MATERIALS
ISSN: 2052-5206
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