position of atom :math:`i` at time :math:`t`. **Note** that fitting
does not have to use the same atoms as the calculation of the
:math:`RMSD`; *e.g.* a protein is usually fitted on the backbone atoms
- (N,C:math:`_{\alpha}`,C), but the :math:`RMSD` can be computed of the
+ (N, C\ :math:`_{\alpha}`, C), but the :math:`RMSD` can be computed of the
backbone or of the whole protein.
Instead of comparing the structures to the initial structure at time