aflow.org: A Web Ecosystem of Databases, Software and Tools

TL;DR

aflow.org is a FAIR-driven web ecosystem that unifies access to the AFLOW materials databases and analytical tools, enabling both casual retrieval and high-throughput workflows. The paper details the repository architecture, including a hierarchical data organization, the AUID-based indexing system, and programmatic interfaces (REST-API, AFLUX) plus OPTIMADE integration for cross-database interoperability. It also introduces the Prototype Encyclopedia and three web applications (AFLOW Online, AFLOW-CHULL Online, AFLOW-ML Online) that lower the barrier to entry by providing online calculation, stability analysis, and ML-based predictions without full software installation. Finally, it emphasizes education and outreach through AFLOW Schools and seminars to broaden global access to materials science software and data.

Abstract

To enable materials databases supporting computational and experimental research, it is critical to develop platforms that both facilitate access to the data and provide the tools used to generate/analyze it - all while considering the diversity of users' experience levels and usage needs. The recently formulated FAIR principles (Findable, Accessible, Interoperable, and Reusable) establish a common framework to aid these efforts. This article describes aflow_org, a web ecosystem developed to provide FAIR - compliant access to the AFLOW databases. Graphical and programmatic retrieval methods are offered, ensuring accessibility for all experience levels and data needs. aflow_org goes beyond data-access by providing applications to important features of the AFLOW software, assisting users in their own calculations without the need to install the entire high-throughput framework. Outreach commitments to provide AFLOW tutorials and materials science education to a global and diverse audiences will also be presented.

Figures (8)

• Figure 1: AFLOW data structure. Illustration of the AFLOW data structure as (a) a human-readable, but unbalanced search tree and (b) a machine-readable, balanced search tree.
• Figure 2: Infrastructure for responding to OPTIMADE queries. Illustration of the workflow for processing an OPTIMADE query. The query is translated to AFLUX (via the generator) for retrieving the data and the AFLOW response is converted to OPTIMADE (via the translator) before returning to the client.
• Figure 3: The AFLOW Search page and materials entry page. (a) Element selection, (b) property filter, and (c) search results of the search page. (d) Thermomechanical properties, (e) structure visualization and symmetry section, and (f) interactive electronic structure of the entry page for spinel CdCr$_2$S$_4$.
• Figure 4: The AFLOW Prototype Encyclopedia web page. ( a) The main web page with a different methods to find specific prototypes, including a search bar. ( b) An example response page when searching for "Nb3Al". The prototype page for Cr$_{3}$Al, the "A15" prototype of Nb$_{3}$Al described in the text can be found at https://www.aflow.org/prototype-encyclopedia/A3B_cP8_223_c_a.html. Each page contains the following: ( c) title, ( d) Jmol viewer, ( e) prototype designations, ( f) a list of compounds/elements exhibiting this structure, ( g) notable comments, ( h) primitive vectors, ( i) basis vectors, ( j) references, ( k) additional references where the structure was found, and ( l) an automatic prototype generator.
• Figure 5: The AFLOW Online interface. (a) The structure input section, (b) a representative feature section, (c) the corresponding output section.