Huge shoutout to my friend & first-coauthor Derek Dardzinski, who handled all the heavy computational lifting. Without his expertise and incredible skills, this work wouldn't have been possible. Thank you💙!

#perovskite #epitaxy @acs.org

To attract fellow synthetic chemists, we made Ogre simple and user-friendly. And if coding isn’t your thing, we’ve got you covered with a desktop app for Windows, Linux, and Mac—no coding required!💻

Though I mainly work with colloidal nanomaterials, especially CsPbBr₃💚, Ogre works for any polar/ionic material. Check out these predictions for oxides grown by thin-film methods!

Ogre can also help decode unknown interfaces, like the complex Bi-Pb-S / CsPbBr₃ match we unravelled here for the first time. Thanks to this tool, we could re-interpret several other epitaxial interfaces involving CsPbBr₃ perovskite.

Ok, but what can you do with Ogre? Here are a few examples. In earlier work, we found that Pb₄S₃Cl₂ & Pb₃S₂Cl₂ grew differently on CsPbCl₃ seeds despite similar chemistry. Ogre revealed it’s because one offers a stable epitaxial interface, while the other does not.

The best part? You DON’T need DFT or supercomputers. For our CsPbBr₃/Pb₄S₃Br₂ test interface, the entire workflow runs in ~2 minutes on a mid-tier laptop, yielding results that match DFT accuracy! 💻⌚️

The interface structures of the remaining candidates are optimized into plausible atomistic models. These are ranked by energy and, if data is available, can be directly compared with experiments (see the CsPbBr₃/Pb₄S₃Br₂ example interface below).

Once an epitaxial orientation is chosen, Ogre slices both materials along different atomic planes to mix & match surface terminations, exploring all possible surface matches. Our filters then screen out the implausible ones, ensuring fast computation.

First, Ogre analyzes the unit cells of the two materials to find all possible commensurate interface 2D-supercells. Small circles = small areas + blue = low strain are signatures of a promising match!

Ogre takes as input the bulk structure of two materials (e.g. CsPbBr₃ & Pb₄S₃Br₂) to:
1️⃣ Find favorable epitaxial orientations
2️⃣ Match possible surface terminations
3️⃣ Identify stable interface models
It outputs optimized and ranked interface models, compatible with VESTA!