We present high-accuracy relativistic investigations of the spectrum Lr, element 103, prompted by planned optical spectroscopy experiments on this rare and short-lived atom. Reliable predictions transition lines are important for planning success these challenging measurements. The coupled cluster approach was used to calculate energies lowest excited states, while combination configuration-int...

Previously we searched for the ab initio global minima of several SixHy clusters by a genetic algorithm in which we used the AM1 semiempirical method to facilitate a rapid energy calculation for the many different cluster geometries explored. However, we found that the AM1 energy ranking significantly differs from the ab initio energy ranking. To better guarantee locating the ab initio global m...