Comment on Orientational Peierls Instability

Abstract
We point out that for a one-dimensional conducting stack of centrosymmetric molecules there are important qualitative differences between an orientational and a positional Peierls instability. A recent Letter by Morawitz, suggesting the presence of an orientational Peierls instability in tetrathiafulvalene-tetracyanoquinodimethane, is criticized in the light of these differences.