The 4-methyl-2,6-bis(phosphomethyl)phenol molecule,
which crystallizes with two water molecules per asymmetric
unit, has approximate twofold symmetry and is
involved in extensive three-dimensional hydrogen bonding
in which every available OH group participates.
The principal dimensions include P--O 1.4981 (13)
and 1.5015 (14) ,~, four P--OH distances in the range
1.5395(14) to 1.5688(13) A, P--C 1.7857(17) and
1.7893 (17) ~k, and O...O intramolecular and intermolecular
hydro.gen-bond distances in the range 2.458 (2) to
2.866 (2) A.