Machine learning has emerged as an invaluable tool in many research areas. In
the present work, we harness this power to predict highly accurate molecular
infrared spectra with unprecedented computational efficiency. To account for
vibrational anharmonic and dynamical effects -- typically neglected by
conventional quantum chemistry approaches -- we base our machine learning
strategy on ab initio molecular dynamics simulations. While these simulations
are usually extremely time consuming even for small molecules, we overcome
these limitations by leveraging the power of a variety of machine learning
techniques, not only accelerating simulations by several orders of magnitude,
but also greatly extending the size of systems that can be treated. To this
end, we develop a molecular dipole moment model based on environment dependent
neural network charges and combine it with the neural network potentials of
Behler and Parrinello. Contrary to the prevalent big data philosophy, we are
able to obtain very accurate machine learning models for the prediction of
infrared spectra based on only a few hundreds of electronic structure reference
points. This is made possible through the introduction of a fully automated
sampling scheme and the use of molecular forces during neural network potential
training. We demonstrate the power of our machine learning approach by applying
it to model the infrared spectra of a methanol molecule, n-alkanes containing
up to 200 atoms and the protonated alanine tripeptide, which at the same time
represents the first application of machine learning techniques to simulate the
dynamics of a peptide. In all these case studies we find excellent agreement
between the infrared spectra predicted via machine learning models and the
respective theoretical and experimental spectra.

本文提出了一种基于机器学习的策略来预测分子红外光谱的方法，建立在从头分子动力学模拟的基础上，利用各种机器学习技术加速模拟并扩展可处理的系统大小，其中包括环境依赖性神经网络电荷的分子偶极矩模型和 Behler 和 Parrinello 的神经网络势能。通过引入完全自动化的采样方案和神经网络势能训练期间的分子力，我们能够仅基于少量的电子结构参考点来获得非常精确的机器学习模型，同时在甲醇分子，含有多达 200 个原子的正构烷和质子化的丙氨酸三肽的情况下，将其应用于模拟红外光谱，并发现与理论和实验光谱具有出色的一致性。