# Frequently Asked Questions ## General ### How do I get started? For installation instructions, check the [installation guide](install). For a quick working example, see the [User Guide](../index). For detailed API usage, refer to the [API documentation](../../modules/index). If your question is not answered here, please submit a Github [Issue][issues_]. ### What hardware does this support? ALCHEMI Toolkit runs on: - CUDA-capable NVIDIA GPUs (Compute Capability 8.0+, i.e. A100 and newer) - CPU execution via NVIDIA Warp (x86 and ARM, including Apple Silicon) For best performance, we recommend CUDA 12+ with driver version 570.xx or newer. See the [installation guide](install) for full prerequisites. ## Dynamics & Simulation ### How do I compute neighbor lists during a simulation? Register a {class}`~nvalchemi.dynamics.hooks.NeighborListHook` on your dynamics engine. The hook recomputes neighbors at the `BEFORE_COMPUTE` stage of every step (with optional Verlet-skin buffering to skip redundant rebuilds). See the [dynamics hooks user guide](../dynamics_hooks) and the {doc}`custom hook example ` for a full walkthrough. ### How do I run a distributed (multi-GPU) pipeline? Chain dynamics stages with the `|` operator to build a {class}`~nvalchemi.dynamics.DistributedPipeline`, then launch with `torchrun`. See the [distributed pipeline API docs](../../modules/dynamics/distributed_pipeline) and the {doc}`distributed pipeline example ` for a complete multi-rank setup. ## Models ### How do I download and use a MACE checkpoint? Use {meth}`MACEWrapper.from_checkpoint() ` with either a foundation-model name (e.g. `"medium-0b2"`) or a local `.pt` path. The method handles downloading automatically. For a full simulation example, see the {doc}`MACE NVT example ` and the [models user guide](../models). ## Interoperability ### How do I convert from ASE Atoms to nvalchemi? Use {meth}`AtomicData.from_atoms() ` to convert an `ase.Atoms` object into an `AtomicData` graph. ASE integer tags are automatically mapped to `AtomCategory` values. See the {doc}`ASE integration example ` for a round-trip workflow (ASE -> nvalchemi -> ASE). [issues_]: https://www.github.com/NVIDIA/nvalchemi-toolkit/issues/new/choose