Bringing Electronic Structure Codes into the Modern Software Ecosystem

We propose a novel framework (“Portobello”) for assimilating Electronic Structure codes into the modern software ecosystem and facilitating an efficient software development process. First we discuss some of the pitfalls of Fortran / Python - centric paradigms, which often lead to flawed design and unwieldy code. We identify a culprit to be the lack of high-level abstraction, which prevents reuse of components, obscures developers' intent, and hinders collaboration. Our new object-oriented framework facilitates all steps of the software developments life-cycle, and is applicable to Fortran-based systems, as well as ones written in C/C++.
Next, we demonstrate how the framework provides a concrete way to address important questions in the physics of Correlated Electronic Structure, as well as implement and test new ideas. Following this approach, we combine A. Kutepov's Fortran-based FlapwMBPT (Full potential LAPW Many-Body Perturbation Theory) with a C++ implementation of CTQMC and Materials Project Pymatgen (crystal and symmetry code) to create a Pythonic charge-self-consistent toy DFT+DMFT program. We demonstrate the calculation of correlated electronic structure, as well as calculation of transport properties, and discuss how the program can be used and extended.