Table 3.

Relevant covalent bond, hydrogen bond and halogen bond lengths and angles in 6–8.

	C–X [Å] [X]	X···O [Å] [O] [R]*	C–X···O	D–H···O [D]	D–H···O [O]
4-IPhNH3H2PO4, 6	1.892 [I1]	3.262 [O12] [0.93]	159.5°	2.930 Å [N8]	165.8° [O10]
				2.860 Å [N8]	173.9° [O10]
				2.707 Å [N8]	173.7° [O13]
				2.598 Å [O11]	155.6° [O10]
				2.533 Å [O12]	160.3° [O13]
4-BrPhNH3H2PO4, 7 (UGISEI, [40])	1.902 [Br1]	3.348 [O1] [0.99]	157.2°	2.951 Å
				2.873 Å
				2.701 Å
				2.582 Å
				2.540 Å
4-ClPhNH3H2PO4, 8	1.742 [Cl1]	3.260 [O2] [1.00]	156.9°	2.920 Å [N8]	164.7° [O10]
				2.844 Å [N8]	175.4° [O10]
				2.678 Å [N8]	174.7° [O13]
				2.590 Å [O11]	161.4° [O10]
				2.534 Å [O12]	158.8° [O13]

^* R = d/(r_X + r_D), see Equation 1. D represents the hydrogen bond donor atom.