. Author manuscript; available in PMC: 2010 Jan 1.

Published in final edited form as: Cryst Growth Des. 2009;9(1):432–441. doi: 10.1021/cg8006712

Table 3.

Halogen bonds in crystal structures 1a–1b, 2a–2c, 3a, and 3c.

SR	Acid^a	Structure #	Halogen bonds	Type of Halogen bond	Halogen bond Distance (Å)	C-X⋯N (°)
1	I-BA	1a	No	----	----	----
1	I-F₄BA	1b	Yes	I⋯N	2.941	170.7
2	I-BA	2a	Yes	I⋯N	3.004	177.1
2	I-F₄BA	2b	Yes	I⋯N	2.812	178.1
2	Br-F₄BA	2c	Yes	Br⋯N	2.840	177.6
3	I-BA	3a	Yes	I⋯O	3.265	178.1
3	Br-F₄BA	3c	No	----	----	----

I-BA = 4-iodobenzoic acid, I-F₄BA = 2,3,5,6-tetrafluoro-4-iodobenzoic acid, and Br-F₄BA = 2,3,5,6-tetrafluoro-4-bromobenzoic acid.