RaySpy

RaySpy App

The RaySpy app combines symbolic computation and effective sparse matrix linear algebra procedures at scale. It is currently the fastest rotational spectra simulator and only spectroscopy simulation app which can derive Hamiltonian matrix models. All code is proprietary. Email for code. Notable features:

• CUDA Acceleration

• Open-shell molecule simulation

• Symbolic computation

The inspiration for this project is the original version of SpecVIEW. The program computes entire rotational spectra, but is limited by lack of updates that support modern parallel programing features, and lack of implementation of newer numerical algorithms for diagonalization. It suffices for most spectra that can be computed quickly. 

Download SpecVIEW, Manual, and Asymmetric-Top Model

Presentations

International Symposium on Molecular Spectroscopy 2025

I was honored to present at the 78th International Symposium on Molecular Spectroscopy (ISMS) this year, sharing my work on high-performance computing for simulations in rotational spectroscopy.

Key takeaways from my talk:

• Hamiltonian matrices enable efficient simulation of rotational spectra.

• Compressed Sparse Row (CSR) format achieves linear memory scaling.

• CUDA-accelerated Jacobi–Davidson diagonalization delivers accurate results in under 1 second.

Looking ahead, I plan to return next year with even faster, simultaneous simulations for a variety of real molecules, along with automatic spectral fitting and automatic extraction of molecular constants.

Our group will also be exploring tensor theory for rovibronic spectra—a direction I’m especially excited about.