A breakthrough has been made in the field of theoretical chemistry by Sandra Luber and her research team at the University of Zurich. They have developed an algorithm that significantly accelerates the computational simulations required to study the dynamics of excited molecules. Previously, these simulations could only be carried out on supercomputers due to their complexity and resource requirements.
The team utilized Piz Daint, a powerful supercomputer, along with software packages like CP2K, which enable real-time calculations of quantum mechanical states in atoms and molecules. By tracking the changes in the wave function of electrons over time after the application of a laser pulse, they were able to observe how the higher energy levels induced by the laser affected the electron occupancy in the molecule.
The researchers aimed to automate and optimize the calculations to avoid time-consuming trial and error. Their algorithm focuses on optimizing the basis sets of functions used by software programs like CP2K for the calculations. They identified two indicators: one to determine the importance of each basis function for calculating the spectrum, and another to assess their significance in accurately tracking quantum mechanical states over time.
To validate their algorithm, the team tested it on various molecules, including molecular hydrogen, water, a silver cluster, and zinc phthalocyanine. The results showed that their new method achieved the same level of precision as conventional simulations but at a much faster pace. The algorithm is not limited to CP2K and can be implemented in other quantum mechanical programs that use atom-centered basis sets.
This breakthrough opens up possibilities for researchers to gain detailed insights into the structure and dynamics of molecules during dynamic processes such as laser excitation. By making these simulations faster and more efficient, scientists can expand their understanding of complex molecular systems and potentially discover new applications in various industries.
What is going on in the excited molecules
Sandra Luber and her research team have achieved a remarkable milestone in computational chemistry. They have developed specialized basis sets that are specifically designed for simulating excited molecular states. This is a significant advancement since such basis sets were not available before. Moreover, these newly generated basis sets are tailored to the specific system and environment of the molecule being studied.
During test simulations of silver atoms within silver clusters, the researchers made an intriguing observation. They found that their algorithm could identify different basis sets for different silver atoms within the cluster. This demonstrates that the algorithm is capable of distinguishing the varying environments within the molecule. For example, if the electron density’s polarization is crucial, the algorithm incorporates polarization functions. Similarly, for regions farther away from the atom, it includes diffuse functions. By discerning the importance of different functions in different areas of the molecule, the algorithm provides valuable insights into the molecule’s chemistry.
With this breakthrough, Luber and her team have made significant progress toward their goal of gaining a comprehensive understanding of the behavior of excited molecules. By utilizing these specialized basis sets, researchers can now delve deeper into the intricacies of excited states and unravel the complex dynamics of molecules during dynamic processes.
Source: University of Zurich