Fig. 5: Simulation of RASER induced via NOE interactions.
From: Through-bond and through-space radiofrequency amplification by stimulated emission of radiation
a Scheme of NOE transfer and main simulation parameters. b Evolution of longitudinal 〈Iz〉 (solid red line), 〈Sz〉 (solid blue line) and transverse 〈I+〉 (dashed red line), 〈S+〉 (dashed blue line) magnetization components of spins I and S. c RASER signal obtained from the simulated 〈I+〉 and 〈S+〉 values. d Evolution of the NMR signals produced from the RASER signal presented in panel (c). Contribution of the spin I in FID is evident but it is 4 orders of magnitude weaker than that of S and would be below the noise level in the real experiment. The NMR parameters of 4a and 4d protons were assumed for I and S, respectively. Parameters for the simulation are:\(\,{\rho }_{{{{\rm{I}}}}}=1/26\,{{{{\rm{s}}}}}^{-1}\), \({\rho }_{{{{\rm{S}}}}}=1/3.81\,{{{{\rm{s}}}}}^{-1}\), \(\sigma =0.0641\,{{{{\rm{s}}}}}^{-1}\), \({\tau }_{{{{\rm{RD}}}}}=44.3{{{\rm{ms}}}}\) (see Supplementary Note 3), \({M}_{0}=\left\langle {\hat{I}}_{{{{\rm{z}}}}}\right\rangle \left(0\right)=0.5\), \(\left\langle {\hat{I}}_{+}\right\rangle \left(0\right)={I}_{{{{\rm{z}}}}}^{{{{\rm{eq}}}}}\), \(\left\langle {\hat{S}}_{{{{\rm{z}}}}}\right\rangle \left(0\right)=\left\langle {\hat{S}}_{+}\right\rangle \left(0\right)={S}_{{{{\rm{z}}}}}^{{{{\rm{eq}}}}}\), \({\nu }_{{{{\rm{I}}}}}={\nu }_{{{{\rm{S}}}}}=1\,{{{{\rm{s}}}}}^{-1}\), \({I}_{{{{\rm{z}}}}}^{{{{\rm{eq}}}}}={S}_{{{{\rm{z}}}}}^{{{{\rm{eq}}}}}=2.42{{{\rm{\cdot }}}}{10}^{-5}\) (numerically equal to thermal polarization of 1H nuclei at 7.05 T magnetic field in absolute units).
