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  • Co-crystals of tetrachloroauric acid and 1,3,5-(methylacetamide)benzene-based tectons: consistent trapping of high energy molecular conformation
Title: Co-crystals of tetrachloroauric acid and 1,3,5-(methylacetamide)benzene-based tectons: consistent trapping of high energy molecular conformation
Co-crystal engineering is a promising method to create new classes of advanced materials. Co-crystal structure prediction is more challenging when one or more of the lattice constituents (tectons) are flexible molecules. This study reports four co-crystals that were prepared by mixing HAuCl 4 or HAuBr 4 with C 3 -symmetric tectons based on a 1,3,5-(methylacetamide)benzene scaffold. X-ray analysis of the co-crystals revealed the presence of three dominant supramolecular interactions; (a) hydrogen bonding between tecton amide NH residues and the AuX 4 − anion, (b) electrostatic stacking of the Au center against the tecton's π-electrons, (c) very short hydrogen bonds within a proton-bridged-carbonyls motif. Within all four co-crystals, the sterically-geared tecton was trapped in a high energy molecular conformation, which increased the number of favorable intermolecular interactions in the lattice. We infer from the results that the likelihood of high energy molecular conformations within a co-crystal increases if there are multiple dominant intermolecular interactions. Application of this generalizable rule should lead to improved crystal structure prediction.  more » « less
Award ID(s):
1708240
NSF-PAR ID:
10338920
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
CrystEngComm
Volume:
24
Issue:
21
ISSN:
1466-8033
Page Range / eLocation ID:
3879 to 3885
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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