Yang Yang Colloquium

Dr. Yang Yang from the University of Wisconsin-Madison will present a Chemistry Colloquium lecture.

Title: Constrained Nuclear-Electronic Orbital (CNEO) Framework: Accurate Vibrational Spectra and Reaction Rates from Efficient Incorporation of Nuclear Quantum Effects

Abstract: Nuclear quantum effects play a significant role in a variety of chemical and biological processes, but it remains challenging to accurately include them in large-scale molecular simulations. Recently, we developed a new molecular dynamics method named constrained nuclear−electronic orbital molecular dynamics (CNEO-MD), which allows for the accurate and efficient incorporation of nuclear quantum effects in molecular simulations. This new MD approach is a combination of our previously developed constrained nuclear−electronic orbital density functional theory (CNEO-DFT) and constrained minimized energy surface molecular dynamics (CMES-MD). We utilized CNEO-MD to calculate the vibrational spectra of a series of molecules and found that it greatly outperforms conventional ab initio molecular dynamics (AIMD), particularly for the vibrational modes with significant hydrogen motion characters. Additionally, by combining the CNEO method with transition state theory, we found that CNEO-DFT can well predict the proton transfer reaction rates. The CNEO framework provides a new way of describing nuclear quantum effects, and its high accuracy and efficiency makes it promising for more complex chemical and biological systems that have significant nuclear quantum effects.