Table 4.

Geometric Properties of F226 Variant C-H···π Interactions.

Residue	Property	F226I	F226L	F226W	HCA IIa	HCA II-CO2b	HCA II-Xec
F66	Distance (Å)d	N/A	N/A	4.5, 4.8	4.4, 4.4	4.0, 4.1	4.1, 4.3
	Anglee	N/A	N/A	120, 120	71, 89	66, 79	83, 64
F95	Distance (Å)	N/A	N/A	3.5	3.8	4.0, 4.0	3.8, 4.1
	Angle (°)	N/A	N/A	115	92	82, 88	79, 87
W97	Distance (Å)	3.3	4.5, 4.7	4.3	4.1	3.7	3.8
	Angle (°)	112	93, 120	120	115	95	114

^aUnbound native HCA II (PDB: 3KS3 (25))

^bCO₂-bound HCA II (PDB: 3D92 (14))

^cXenon-bound HCA II (PDB: 3CYU (15))

^dDistance between carbon atoms and ring center of interacting sidechains

^eAngles measured between ring atom, ring center and carbon atom of interacting sidechains