  We present local structural evidence supporting the presence of charge
inhomogeneities in the CuO2 planes of underdoped La2-xSrxCuO4. High-resolution
atomic pair distribution functions have been obtained from neutron powder
diffraction data over the range of doping 0 < x < 0.30 at 10 K. Despite the
average structure getting less orthorhombic we see a broadening of the in-plane
Cu-O bond distribution as a function of doping up to optimal doping. Thereafter
the peak abruptly sharpens. Complementary evidence is also evident from the
observation of octahedral tilt disorder in the PDF at higher atomic separation.
This suggests a crossover from a charge inhomogeneous state at and below
optimal doping to a homogeneous charge state above optimal doping. The strong
response of the local structure to the charge-state implies a strong
electron-lattice coupling in these materials.
