Pchem, how do I love thee?
Let me count the ways

1. Pchem connects abstract concepts to concrete reality.

The concept of the wave nature of light and matter is very abstract. It is not directly measurable. But the mathematics of interacting waves allows us to predict the interactions of light and matter. This is called spectroscopy.

Your eyes are pigment-based spectrometers detecting light at different wavelengths giving you the ability to perceive what we call color.

From these abstract wave equations we get concrete products like laser pointers and digital cameras. And I love it!

2. Pchem simulates natural phenomena well.

Some of the spectroscopic simulations I have seen in pchem have been truly amazing. To appreciate this, one may need a micro-course in statistics.

The R² value can be thought of as “how much scatter in the data is explained by your model”.

A decent calibration curve in an environmental lab or water quality lab will have a 99.95% R² value, meaning that the calibration model captures 99.95% of the scatter in the data.

The R² value for modeling the rotational-vibrational spectroscopic transitions in carbon monoxide is often 99.9996% or better. This means our pchem model for molecular vibration and rotation is capable of capturing over 99.999% of the variation in the data.  That’s crazy-good! In fact, this model is so detailed, we can tell how much the CO bond length stretches as it spins faster and faster. I love that!

OK. So the wave function concept allows us to simulate nature and to produce exciting gadgets. But what IS the wave function, ontologically?

This is perhaps the most exciting thing about pchem. It transforms your imagination. I am drawn to think deeply about the wave nature of matter, the balance of Coulombic attraction and repulsion, the coupling of intrinsic angular momentum.

What IS the angular momentum of a WAVE?

Where IS the mass in a WAVE?

What (or WHO) sustains these never-decaying ground state wave functions?

Amazing questions for an amazing life of the mind, which is another reason I love pchem.