The Interoperability Challenge in DFT Workflows Across Implementations

TL;DR

This paper introduces a standardized input/output schema to improve interoperability and cross-validation among various DFT codes and workflow managers, facilitating reproducible high-throughput materials screening.

Contribution

It presents a universal schema for DFT workflows, enabling engine-agnostic execution and addressing challenges in comparing energetics across different DFT implementations.

Findings

Developed a common input/output standard for DFT workflows.

Successfully demonstrated cross-code calculations of battery materials.

Identified challenges in aligning electronic properties across DFT engines.

Abstract

Interoperability and cross-validation remains a significant challenge in the computational materials discovery community. In this context, we introduce a common input/output standard designed for internal translation by various workflow managers (AiiDA, PerQueue, Pipeline Pilot, and SimStack) to produce results in a unified schema. This standard aims to enable engine-agnostic workflow execution across multiple density functional theory (DFT) codes, including CASTEP, GPAW, Quantum ESPRESSO, and VASP. As a demonstration, we have implemented a workflow to calculate the open-circuit voltage across several battery cathode materials using the proposed universal input/output schema. We analyze and resolve the challenges of reconciling energetics computed by different DFT engines and document the code-specific idiosyncrasies that make straightforward comparisons difficult. Motivated by these challenges, we outline general design principles for robust automated DFT workflows. This work represents a practical step towards more reproducible and interoperable workflows for high-throughput materials screening, while highlighting challenges of aligning electronic properties, especially for non-pristine structures.