  Planned optical spectroscopy experiments in lawrencium (Lr, Z = 103) require
accurate theoretical predictions of the location of spectral lines in order to
narrow the experimental search window. We present ab initio calculations of the
atomic energy levels, transition amplitudes and g-factors for lawrencium, as
well as its lighter homologue lutetium (Lu, Z = 71). We use the configuration
interaction with many-body perturbation-theory (CI+MBPT) method to calculate
energy levels and transition properties, and benchmark the accuracy of our
predicted energies using relativistic coupled-cluster codes. Our results are
numerically converged and in close agreement with experimentally measured
energy levels for Lu, and we expect a similar accuracy for Lr. These systematic
calculations have identified multiple transitions of experimental utility and
will serve to guide future experimental studies of Lr.
