CRASY

Correlated Rotational Alignment Spectroscopy

Visualizing Rotational Wave Packets (superposition of spherical harmonics)

Attached below is a Python script to display spherical harmonics and spherical harmonic superpositions. Spherical harmonics are the angular wavefunctions (“eigenfunctions”) used to describe rotational states of molecules and the angular properties of electrons in atoms (i.e., “atomic orbitals”). A single eigenfunction of the Schrödinger equation is time-independent but dynamics can be described by a superposition (sum) of eigenfunctions. E.g., the square of a sum of spherical harmonics predicts the angular orientation of a molecule as function of time. To use the script, you need to have a functional version […]

CRASY: Observing Rotation in the Time Domain

Below, I posted a short video explaining how we observe rotation in the time domain. Please note that the video does not explain the quantum mechanical principles required to describe molecular rotation, but gives a pseudo-classical picture. This picture does not explain why molecular rotation is quantized or how we can relate rotational frequencies to molecular structure.

CRASY Data Analysis

Here is a guide for CRASY data analysis, written for a UNIST lab course: PC_lab_course_CRASY_Schultz.pdf. You can find an installation guide for the data analysis software on page 6 and a guide for CRASY data analysis on the following pages. If you want to learn more about the CRASY experiment, navigate to the crasy.org landing page. Required Software You will require the following software: (1) Python (I suggest to install the “Miniconda” package.) (2) The crasyPlots program. If you have trouble installing or running the software, watch the walk-through video below.   Data […]

Scientific writing Style-Guide

The following are some resources that may help you with your scientific writing. Scientific writing can be a challenge even for native writers, so don’t despair. Practice makes perfect and you have to write to learn to write. If you have to write a report, please use a template and submit your report with double line spacing for easier correction. I propose the template from JACS for MS Word or Latex. To master structure and style, please refer to the relevant Style Guides. Here is a short 1-page cheat sheet […]

IR Correlation Table and other Lab Course Material

The introduction slides for the lab course can be found on the UNIST Blackboard system. Vibrational absorption frequencies for common chemical groups are listed in the IR_correlation_table. Relevant vibrational Raman reference spectra [1] are summarized in this document: Literature Raman spectra. You can ask questions to the teaching assistants 인호 (heo528@unist.ac.kr) and Begum Ozer (begumrukiyeozer@gmail.com). [1] SDBSWeb : http://sdbs.db.aist.go.jp (National Institute of Advanced Industrial Science and Technology, Aug. 9, 2016)