Abaqus .odb file format

Dear All, I'm working on molecular mechanics and FEM, I got abaqus x.odb file and I want to extract eigenvector for every single mode which will help me in next step to compute protein B-factor (Boltzman factor). I order to do that, I need to know the .odb file format which will be helpfull for me to write a code to extract the mode. Thank you in adavance for your response.