deletions | additions       diff --git a/sigma_i__HB_is_the__.tex b/sigma_i__HB_is_the__.tex  index 01dda05..fe7dc89 100644  --- a/sigma_i__HB_is_the__.tex  +++ b/sigma_i__HB_is_the__.tex 
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$\sigma^i_{HB}$ $\Delta\sigma^i_{HB}$  is the effect of hydrogen bonding to the H(N) and O(C) atoms of residue $i$, respectively, on the chemical shielding of the backbone amide atoms (i.e. this term is zero for CB) and has two contribution. $$ \sigma^i_{HB}=\sigma^i_{1^\circ HB}(r_{\mathrm{HO}},\theta_{\mathrm{H}},\rho_{\mathrm{H}})+\sigma^i_{2^\circ $$\Delta \sigma^i_{HB}=\Delta\sigma^i_{1^\circ HB}(r_{\mathrm{HO}},\theta_{\mathrm{H}},\rho_{\mathrm{H}})+\Delta\sigma^i_{2^\circ  HB}(r_{\mathrm{OH}},\theta_{\mathrm{O}},\rho_{\mathrm{O}})$$ Here $r_{\mathrm{HO}}$ refers to the OH HB distance involving the amide H and θH and ρH are the corresponding angles (Figure 2). Similarly, $r_{\mathrm{OH}}$ refers to the OH HB distance involving the amide O and $\theta_{\mathrm{O}}$ and $\rho_{\mathrm{O}}$ are the corresponding angles. For H(N), N, CA, and HA is computed using the amide proton of residue $i$, i.e. $\sigma^i_{HB}=\sigma^i_{1^\circ $\Delta\sigma^i_{1^\circ  HB}(r_{\mathrm{H(i)O}},\theta_{\mathrm{H}i},\rho_{\mathrm{H}i})$, while for C’, which is bonded to the N atom of the subsequent residue, $\sigma^i_{1^\circ $\Delta\sigma^i_{1^\circ  HB}$ is computed using the amide proton of residue $i+1$. is computed for C’, HA and CA using the O of residue i, while for H(N) and N, it is computed using the O(C) atom of the preceding $(i-1)$ residue.