Shifts in the X-ray K-absorption edge of copper due to chemical effects

We have investigated the K-absorption edge of copper in the metal and its compounds. It is found that owing to chemical combination the K-absorption edge of copper is, in general, shifted towards the high-energy side by 2-10 ev. However, in the case of Cu 2 O the shift is small and towards the low-energy side. A white line at the absorption edge has been detected for CuO, CuCO 3 , Cu[CH 3 COO] 2 and Cu 3 [Fe(CN) 6 ] 2 .