Doping evolution of the linear T coefficients of the resisitivity at high and low temperatures (α

(a)
Experiment (see Figure 3) versus theory.
α_{1}(0)=C[N_{4M}/N_{M}]
and
α_{1}(∞)=C[N_{Cu}/N_{M}]
where
N_{M} is the total number of metallic Cu sites,
N_{4M} is the number of Cu atoms inside the
non-overlapping 4-Cu-site plaquettes, and
N_{Cu} is the total number of planar Cu sites.
The low and high temperature linear T scattering rates
arise from phonons and are given by
1/τ(0)~N_{4M}T and
1/τ(∞)~N_{Cu}T, respectively.
Dividing by the total number of
charge carriers, N_{M}, leads to
α_{1}(0) and α_{1}(∞).
For C=0.904 micro-ohm-cm/K,
the RMS and maximum absolute errors are
0.017 and 0.17 micro-ohm-cm/K, respectively.
**There is exactly one adjustable parameter, C**

(b) plot of the ratio
α_{1}(0)/α_{1}(∞).
C cancels out here, so there are **zero adjustable parameters.**
For doping x < 0.187, N_{4M}=N_{M} because there are no
overlapping plaquettes.
Hence, α_{1}(0)=C.
The start of plaquette overlap at x=0.187 (vertical dashed line)
leads to the sharp discontinuity in α_{1}(0) there.
Since N_{M}→ N_{Cu}
with increasing doping,
α_{1}(∞) at high doping tends to
the same constant C, as observed.

(a) and (b) are the main results of the paper.