Introduction to Quantum Chemistry Simulations with ORCA


Instructor: Xin Yang

Time: Friday, March 12, 10:00AM-12:30PM

Location: Zoom session only

Prerequisites: Basic Linux and Physical Chemistry

This course provides a brief introduction to quantum chemistry simulations with ORCA, a free toacademics quantum chemistry software package.ORCA offers a wide range of methods for modeling chemical compounds and processes, including the relatively new local correlation methods (DPLNO). In this course, Quantum Mechanics (QM) simulation related concepts such as the ab initio and DFT level of theory, basis sets, effective core potentials (ECP), solvation, and relativistic effects will be introduced. By taking this course, you will be able to gain hands-on experience in using ORCA to setup, run, and analyze the results for DFT calculations, including geometry optimization, vibrational frequencies/IR spectra and UV-Vis spectra.

Course Materials (Spring 2021)

Presentation slides

The presentation slides are available as downloadable PDF files.

  • Introduction to Quantum Chemistry Simulations with ORCA: PDF
  • Introduction to Quantum Chemistry Simulations with ORCA tutorial: PDF
  • Introduction to Quantum Chemistry Simulations with ORCA tutorial files: zip
  • Additional information about ORCA can be found at: ORCA


This course focuses on the following topics:

  • Basic introduction to quantum mechanics
  • How to set up and run ORCA calculations
  • Using Avogadro and Molden as a GUI
  • Single-point calculations
  • Geometry optimizations
  • Frequency calculations
  • Excited state calculations
  • Spectroscopic properties
We gratefully acknowledge support from NSF award #1925764, CC* Team: SWEETER -- SouthWest Expertise in Expanding, Training, Education and Research, Texas A&M's High Performance Research Computing, and Texas A&M's Laboratory for Molecular Simulation.