The thermopower of KMo6O17 was measured in the range 10-250K under fie
lds up to 8 T. A large positive increase of thermopower along the (a,b
) plane is observed below the charge density wave transition both with
field perpendicular and parallel to the layers whereas above the tran
sition the thermopower is field independent. The results are discussed
in relation to the magnetoresistance data and the properties of the F
ermi surface and the band structure in the CDW state.