Neutron diffraction study on the crystal structures of deuterated and non-deuterated LiTlC₄H₄O₆·H₂O (LTT)

Abstract

Crystal structure of deuterated LiTlC₄H₄O₆ · H₂O was analyzed in the paraelectric phase by using neutron diffraction method and the result was compared with that of non-deuterated LTT reported by Kay. It was clarified that no remarkable difference exists between D- and H-salts but both the salts show characteristic elongation of thermal ellipsoid in one of the hydroxyl hydrogen atom in the tartrate molecule. Preliminary neutron diffraction study proved that space group of D-LTT is P2₁ in the ferroelectric phase. The symmetry change is similar to that observed in Rochelle salt, but monoclinic spontaneous strain was not detected at 6 K within the experimental error.

Key Words:

• Neutron diffraction
• crystal structure
• deuterated material
• isotope effect
• LTT