X-ray-scattering measurements on TTF-TCNQ (tetrathiafulvalene-tetracyanoquinodimethane) above 54 K clearly reveal a new one-dimensional scattering at the wave vector (0.59±0.02)6* interpreted as 4fc F scattering and attributed to an additional phonon anomaly which also condenses at low temperature. This 4fc F scattering is still clearly visible at 220 K in contrast to the earlier reported 2fe F scattering which is found to disappear at 150 K in agreement with the neutron scattering results of Shirane et al %

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