arXiv subjects

Nico Hotz

Publications and source records attributed to Nico Hotz.

4 recordsLinked to original sources

arXiv2026

Disorder viscosity correction approach to calculate spinodal temperature and wavelength

Spinodal decomposition, a key mechanism to microstructure formation in materials, has long posed challenges for predictive modeling, due to the need for parameter-free approaches that accurately capture local energy landscapes. In this work, we propose an approach to predict spinodal behavior by introducing a disorder viscosity correction to bulk free energies computed from finite, small, representative cells. We approximate the energy penalty required to transition into a disordered state to enable the stabilization of locally concave bulk free energy regions - essential for interface formation - while suppressing long-range concentration fluctuations. This approximation circumvents the complexity of full ab initio parameterization of interfacial properties and is well-suited for high-throughput and machine-learning frameworks. Our approach captures the necessary physics underpinning spinodal kinetics, offering a scalable route to predict spinodal regions in compositionally complex and high-entropy materials.

cond-mat.mtrl-sci↗

arXiv2025

AFLOW4: heading toward disorder

AFLOW4 is the latest iteration of the AFLOW toolkit, specifically tailored to study high-entropy disordered materials. This upgrade includes innovative features like the Soliquidy module, based on the Euclidean transport cost between disordered and ordered material states. AFLOW4 can calculate dielectric functions to understand optical and electronic properties of disordered ceramics. The newly introduced human-readable data export feature ensures the uncomplicated incorporation of AFLOW4 in diverse automated workflows. Features relevant to high-entropy research, like prototype identification, partial occupation method, convex hull calculation, and enthalpy corrections based on local atomic environments, have been improved and exhibit substantial speed-up. Together, these enhancements represent a step forward for AFLOW as a valuable tool for research of high-entropy materials.

cond-mat.mtrl-sci↗

arXiv2025

Soliquidy: a descriptor for atomic geometrical confusion

Tailoring material properties often requires understanding the solidification process. Herein, we introduce the geometric descriptor Soliquidy, which numerically captures the Euclidean transport cost between the translationally disordered versus ordered states of a materials. As a testbed, we apply Soliquidy to the classification of glass-forming metal alloys. By extending and combining an experimental library of metallic thin-films (glass/no-glass) with the aflow.org computational database (geometrical and energetic information of mixtures) we found that the combination of Soliquity and formation enthalpies generates an effective classifier for glass formation. Such classifier is then used to tackle a public dataset of metallic glasses showing that the glass-agnostic assumptions of Soliquity can be useful for understanding kinetically-controlled phase transitions.

cond-mat.mtrl-sci↗

arXiv2023

A priori procedure to establish spinodal decomposition in alloys

Spinodal decomposition can improve a number of essential properties in materials, especially hardness. Yet, the theoretical prediction of the onset of this phenomenon (e.g., temperature) and its microstructure (e.g., wavelength) often requires input parameters coming from costly and time-consuming experimental efforts, hindering rational materials optimization. Here, we present a procedure where such parameters are not derived from experiments. First, we calculate the spinodal temperature by modeling nucleation in the solid solution while approaching the spinode boundary. Then, we compute the spinodal wavelength self-consistently using a few reasonable approximations. Our results show remarkable agreement with experiments and, for NiRh, the calculated yield strength due to spinodal microstructures surpasses even those of Ni-based superalloys. We believe that this procedure will accelerate the exploration of the complex materials experiencing spinodal decomposition, critical for their macroscopic properties.

cond-mat.mtrl-sci↗