# Textbook module

This is a collection of textbook formulas.

## Functions

- brokensymm.m
- Exchange coupling estimation from a pair of DFT logs using Yamaguchi equation.

- levelpop.m
- Energy levels and their populations for a single spin

- rlx_csa.m
- Redfield rates for CSA relaxation.

- rlx_dd_csa.m
- Redfield theory expressions for CSA-DD-CSA rates relevant to TROSY effect.

- rlx_dip.m
- Redfield theory expressions for dipolar relaxation and cross-relaxation rates.

- rlx_hfc.m
- Redfield theory expressions for hyperfine relaxation and cross-relaxation rates.

- rlx_nqi.m
- Redfield rates for quadrupolar relaxation

- r1csa2tauc.m
- Rotational correlation time estimate for CSA dominated longitudinal relaxation.

- r2csa2tauc.m
- Rotational correlation time estimate for CSA dominated transverse relaxation.

- quad_shift.m
- Second order shift due to strong quadrupolar interaction.

*Version 2.7, authors: Ilya Kuprov*