“…21 The microscopic distribution of oxygen [111] is neither easily observed [112,113,114] nor easily controlled [115]: Experimentally, oxygen content and distribution are adjusted by means of (oxygen partial) pressure, temperature and sufficient holding time to achieve thermal equilibrium [116]. 22 The T c depression is believed to arise from a redistribution of doping charge in the CuO 2 layer stacks from the interior to the outer CuO 2 layers [117] which has been confirmed by NMR measurements [118,119]. Based on these experimental results, a reasonable theoretical description of T c (n) has recently been modeled in a phenomenological Ginzburg-Landau free energy approach [120].…”