Molecular and crystal structure of tris(hydroxymethyl)aminomethane

C4HnNO3, orthorhombic, Pna21, a = 8.807(6) Å, b = 8.872(7)Å, c = 7.709(7)Å, V= 602Å3,Z= 4, Dc = 1.335, Dm = 1.335 gcm-3 (in butyl alcohol), λ(Cukα) = 1.5418Å. The structure was solved using MULTAN and refined by the full matrix least-squares method to a final R value of 0.080. The central carbon atom is coordinated tetrahedrally by the carbon atoms of hydroxymethyls and the nitrogen atom of an amino group. The NH2–C–(CH2OH)3 tetrahedra show marked departures from a regular tetrahedron.