A new family of sodium aluminodiphosphonates (diphosphonate = 1-hydroxyethylidenediphosphonate) has been synthesised hydrothermally at 433 K for 15 days. By altering the aluminium source, two different morphologies, namely hexagonal tubular and solid morphology, have been obtained, and the corresponding crystals were named as DLES-Alt and DLES-Als, respectively. Under the synthesis condition for DLES-Alt, if the reaction time was changed to 7 days, a small amount of crystals with the solid morphology accompanying DLES-Alt were observed, and designated as DLES-Alts. Meanwhile, crystals with a plate-like morphology (designated as DLES-Alp) were always the accompanying phase of the main phase of DLES-Alt or DLES-As. All of the crystals were isostructures. A hexagonal ring containing a propeller-like chiral motif along [0 0 1] is a common characteristic of these crystals. Being a representative case, the crystallographic data of DLES-Alt is trigonal (space group P-3), with cell parameters at 293 K as follows: a = 17.853(4), b = 17.853(4), c = 8.823(4)Angstrom, V = 2435.3(14) Angstrom(3), and Z = 6. (C) 2004 Elsevier B.V. All rights reserved.