Module: ttsketch

Description	Usage
TT-Metadynamics, a variant of metadynamics where the bias potential is periodically compressed into a tensor train (TT); useful for high-dimensional bias potentials (many CVs)
Authors: Nils E. Strand, Siyao Yang, Yuehaw Khoo, and Aaron R. Dinner

Details

Overview

This module implements tensor train metadynamics (TT-MetaD), a method that represents the metadynamics bias potential as a tensor train (TT) rather than as a sum of Gaussian hills. The accumulated Gaussian hills are periodically compressed into a low-rank TT approximation using the TT-Sketch algorithm, keeping memory and evaluation cost bounded throughout long simulations.

For the full algorithmic details see the paper: https://arxiv.org/abs/2603.13549

Installation

This module requires the ITensor library (v3) with HDF5 support.

Building ITensor

Follow the ITensor installation instructions. Copy options.mk to the ITensor source directory and edit it to match your compiler and LAPACK/BLAS setup. Then build:

cd /path/to/ITensor
cp options.mk.sample options.mk
# edit options.mk as needed
make

Building PLUMED with ttsketch

Once ITensor is built, configure PLUMED from its source directory. Adjust library paths and flags to match your options.mk:

./configure --enable-modules=ttsketch --enable-libitensor \
    LDFLAGS="-L/path/to/ITensor/lib" \
    CPPFLAGS="-I/path/to/ITensor -DITENSOR_USE_HDF5 -DITENSOR_USE_OMP -D__ITENSOR_LAPACK_WRAP_h" \
    LIBS="-litensor -lmkl_intel_lp64 -lmkl_sequential -lmkl_core -lhdf5 -lhdf5_hl" \
    CXXFLAGS="-O3 -fconcepts"

The flags above assume Intel MKL for LAPACK/BLAS. If you use OpenBLAS or another provider, replace the -lmkl_* flags accordingly.

Actions

The following actions are part of this module

Tags

BIAS

BIAS: bias potentials that can be used to force rare events to occur in MD simulations

Name	Description	Tags
TTMETAD	Performs metadynamics with a tensor-train representation of the bias potential.	BIAS