Relevance of nonadiabatic effects in TiOCl

Abstract

We analyze the effect of the phonon dynamics on a recently proposed model for the uniform-incommensurate transition seen in TiOX compounds. The study is based on a recently developed formalism for nonadiabatic spin-Peierls systems based on bosonization and a mean field RPA approximation for the interchain coupling. To reproduce the measured low temperature spin gap, a spin-phonon coupling quite bigger than the one predicted from an adiabatic approach is required. This high value is compatible with the renormalization of the phonons in the high temperature phase seen in inelastic x-ray experiments. Our theory accounts for the temperature of the incommensurate transition and the value of the incommensurate wave vector at the transition point.

4 pages, 2 figures

References in corpus (8)

• Zero-field incommensurate spin-Peierls phase with interchain frustration in TiOCl
• Mean Field theory of the spin-Peierls transition
• X-ray Scattering Study of the spin-Peierls transition and soft phonon behavior in TiOCl
• Microscopic model for transitions from Mott to spin-Peierls insulator in TiOCl
• The spin-Peierls transition beyond the adiabatic approximation
• Density functional study of the electronic and vibrational properties of TiOCl
• Microscopic theory for the incommensurate transition in TiOCl
• Theoretical study of the magnetism in the incommensurate phase of TiOCl

Cited by in corpus (1)

• Incommensurate spin Luttinger liquid phase in a model for the spin-Peierls materials TiOBr and TiOCl