Table 1. Crystal parameters of compounds investigated in this study.

Adapted from refs. [44–47].

	O-Phospho-L-serine	Ca(II)(O-phospho-L-serine)H2O	(O-Phospho-DL-serine)H2O	O-Phospho-L-threonine
CSD ID	SERPOP01	TEGLUM	SERIPH10	POTHRE01
Formula	C3H8NO6P	Ca(C3H6NO6P)(H2O)	C3H8NO6P(H2O)	C4H10NO6P
MW (g/mol)	185.06816	241.14556	185.06816	199.1
T (K)	283–303	296	283–303	295
Crystal System	Orthorhombic	Monoclinic	Monoclinic	Orthorhombic
Space Group	P212121	P21	C2/c	P212121
a (Å)	7.767	5.534	18.473	6.709
b (Å)	10.167	12.759	8.327	9.854
c (Å)	9.136	5.74	12.3	11.776
α (deg)	90	90	90	90
β(deg)	90	104.77	120.72	90
γ (deg)	90	90	90	90
V (Å3)	718.657	391.9	1626	777.9
Z, Z′	4, 1	2, 1	8, 1	4, 1
Dc (g/cm3)	1.709	2.044	1.661	1.7
Crystal size (mm)	0.2 × 0.2 × 0.4	0.2 × 0.1 × 0.005	0.15 × 0.15 × 0.5	0.35 × 0.15 × 0.15
Crystal Habit	Blocks	Plate	Blocks	Needle
Crystal Color	Colorless	Colorless	Colorless	Colorless
R-Factor (%)	2.7	2.4	3.0	2.6