So this is the first note in the lab notebook:

Working on fitting the ab-plane
First some nomenclature:
A1 = Ni1-O peak
A2 = Ni2-O peak
A3 = Ni2-Y peak
A4 = Ni2-Ba peak
A5 = Ni1-Ba peak
A6 = Ni1-Cu peak
A7 = Ni2-Cu peak

and

x=consentration of Ni on Cu1 per layer
(x-1)/2 = consentration of Ni on Cu2 per layer

now, using this nomenclature, and an S02 = 3/4

A2 = 3-2A1
A3 = 0.5 (A2)
A4 = A3
A5 = 2A1
A6 = A5
A7 = A2

Now the multi-leg needs to be done:
Add together multi's within +- 0.05 angs.
Only include multi's within ~5% of the max amplitude peak.
Remember to add similar paths
Only add multi's which start in the ab-plane
Also, constrain by (1) (# of same multi-leg) (concentration per layer)

N1 (c-axis: 113,114) (ab-plane: 130,131) Grown in Ar
N2 (c-axis: 120,121) (ab-plane: 133,134) Grown in air; annealed in O2
N3 (c-axis: 123,124) (ab-plane: 137) Grown in air; annealed in Ar; annealed in O2
N4 (c-axis: 127,128,129) (ab-plane: 138) Grown in air; annealed in Ar; cooled in Ar)