Pepper with negative hyperfine values?
Posted: Wed Apr 26, 2017 3:42 pm
Hi, running pepper with negative hyperfine values for some axes gives spectra that do not match my expectations, or my own Matlab code. I will paste in an explicit example below. I expect this spectra to have a narrow central line (for 14N = 0), and the two (14N = +-1) other peaks to form a Pake doublet like pattern around the narrow central line. Instead it looks like the -20 MHz hyperfine axes are treated as +20?
Nx.g = [2.005 2.005 2.005];
Nx.lwpp = 0.1; %mT for field sweeps
Nx = nucspinadd(Nx,'14N',[-20 -20 49]); % MHZ
%------------------------------------------------------------
Exp1.mwFreq = 33.94465;
Exp1.Harmonic = 0;
Exp1.Range = [1199.0 1220.9893];
Exp1.nPoints = 2048;
Opt.Method = 'perturb2';
Opt2.Method = 'matrix';
% Simulate and plot frequency-sweep spectrum
[B,spec]=pepper(Nx,Exp1,Opt);
[B2,spec2]=pepper(Nx,Exp1,Opt2);
Nx.g = [2.005 2.005 2.005];
Nx.lwpp = 0.1; %mT for field sweeps
Nx = nucspinadd(Nx,'14N',[-20 -20 49]); % MHZ
%------------------------------------------------------------
Exp1.mwFreq = 33.94465;
Exp1.Harmonic = 0;
Exp1.Range = [1199.0 1220.9893];
Exp1.nPoints = 2048;
Opt.Method = 'perturb2';
Opt2.Method = 'matrix';
% Simulate and plot frequency-sweep spectrum
[B,spec]=pepper(Nx,Exp1,Opt);
[B2,spec2]=pepper(Nx,Exp1,Opt2);