Research - Department of Chemistry
Quantum Chemistry
In the quantum chemistry group, we develop models and methods for molecular electronic-structure theory at mean-field and correlated levels of theory.
The electronic-structure models are implemented in the open-source software package eT.
Research topics and project opportunities
We focus on the description of a range of different areas in chemistry.
We offer master's projects within method and software development and in the application of computational methods.
The exact formulation of projects can be tailored to students' programming competence and interests. Below are examples of the research we do.
Molecules in optical cavities
Placing a molecule between two small mirrors, in a so-called optical cavity, can significantly modify its properties.
The strong interaction between light and matter in these cavities creates mixed light-matter states known as polaritons. Polaritonic states have different properties compared to pure electronic states, allowing for new and interesting chemistry. In the quantum chemistry group at NTNU, we develop a wide range of quantum electrodynamics (QED) models to describe molecules in optical and plasmonic cavities.
Molecules in open quantum systems
In quantum chemistry, we generally consider closed molecular systems, i.e., we have conservation of energy and number of electrons. However, in reality, molecules interact with their surroundings which may result in fluctuations of energy and electrons in the molecule.
By quantum mechanically describing molecules as open quantum systems, we may gain a fundamental understanding of how such fluctuations modify molecular properties. This is relevant for applications in topics such as heterogeneous catalysis, molecular electronics, and electron transfer theory.
Photoinduced molecular dynamics
Following an electronic excitation, a molecule can relax back to the ground state, or it can undergo dissociation or conformational changes. Accurate theoretical modeling is required to understand the dynamics that molecules undergo after the absorption of light. Coupled cluster theory defines some of the most accurate models in quantum chemistry.
However, the standard coupled cluster models are known to fail to describe the potential energy surfaces of molecules when they intersect. These intersections are essential to describe the nuclear dynamics following electronic excitations. We develop a similarity-constrained coupled cluster theory that resolves these issues and collaborates with experimental groups on ultrafast spectroscopy.
Quantum chemistry for large molecular systems
The polynomial scaling of correlated electronic-structure models renders them too expensive for many molecular systems of interest. One way to extend the applicability range of these models is through multilevel approaches, where important regions of the molecular system are treated at a high level of theory, and less important parts are treated at a lower level of theory.
In the quantum chemistry group, we develop multilevel coupled cluster models to accurately describe molecular properties in larger molecular systems, in particular the molecular responses to external electric or magnetic fields.
Teaching
Our group is in charge of the following three courses:
- KJ1041 - Physical chemistry: molecular structure
- TKJ4170 - Quantum Chemistry
- KJ8206 - Advanced Quantum Chemical Methods
For more information about each course see the respective course websites (links).
For recommendations to other relevant courses for our group, please contact us.
Funding
- ERC Advanced Grant 2020
- NFR Young Researcher Talents
- Onsager Fellowship