This structure is no longer valid and should not be used in a scientific context. The lines are caused by incorrect bonds between atoms. I don't know whether charge assignment (or force field application) was performed on the structure in the image, but it appears that an extra bond has been added to an atom outside the image. If the force field was applied incorrectly or if the atom is undefined in terms of parameters, you will encounter absurd distances. I encountered this situation when preparing structures due to the “fake atom” assignment in the software I was using. I prevented this by changing the software I used during the preparation process.