I have tried to look at the unit cell information of pdb Id :3HR2. It is a fiber diffraction structure of collagen with only CA coordinates. I tried using different programs like VMD to visualise unit cell, the unit cell is at the  beginning of N terminus in agreement with experimental paper. Whereas in Chimera it is not the case. How can I visualize the unit cell of 3HR2 structure in Chimera and also number of molecules within one unit cell?