deletions | additions       diff --git a/Delta_sigma_i__1_circ__.tex b/Delta_sigma_i__1_circ__.tex  index f134622..1b2b5e1 100644  --- a/Delta_sigma_i__1_circ__.tex  +++ b/Delta_sigma_i__1_circ__.tex 
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$\Delta\sigma^i_{1^\circ HB}$ is computed as the change in chemical shielding of the corresponding atom in the donor molecule N-methyl acetamide (NMA) due to the amide proton hydrogen bonding to an acceptor NMA, methanol, or acetate molecule (Figure 2). \ref{fig:HB}).  $\Delta\sigma^i_{2^\circ HB}$ is the change in chemical shielding of an atom in an acceptor NMA due to the carbonyl oxygen hydrogen bonding to a donor NMA molecule. These values are taken from the same NMA dimer calculations used to compute $\Delta\sigma^i_{1^\circ HB}$ (Figure 2a). In both cases is C$\alpha$ defined as the methyl C bonded to N in the NMA molecule and the chemical shielding of H$\alpha$ is taken as the average of the H chemical shieldings for that methyl group.  The range of bond lengths and angles considered is described in Section 3.3.   
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