The incommensurate charge density modulation in 2-dimensional conducting sy
stems leads to characteristic profiles of the charge density and to charact
eristic distributions of electric field gradient (EFQ) tensor components wh
ich can be probed by Knight-shift and nuclear quadrupole interaction measur
ements, respectively The Fourier expansion of the charge density reveals ho
w the density distribution translates into EFG tensor component distributio
ns. Lineshape simulations for I=1 illustrate that the local model is inadeq
uate.