Ab Initio Heavy Element Composite Methodologies

Providing the correct qualitiative description much less achieving quantitative accuracy for the prediction of energetic properties can become challenging for the lanthanides and actinides due to increasing computational costs and, typically, increasing complexity of the methodologies required. Developments by our group and applications that have provided insight about both energetic predictions for species of the lower part of the periodic table and the theoretical strategies used for the predictions will be highlighted. Specifically, we will discuss the heavy element correlation consistent Composite Approach (<i>f-</i>ccCA) and the super correlation consistent Composite Approach (s-ccCA), which have been designed for elements of the lower perioidic table. These methods are build upon the main group and transition metal correlation consistent composite approaches, which have been effectively utilized for many hundreds of species. Successes and challenges in describing heavy elements will be overviewed.