# Overtone dante.m

Overtone DANTE experiment with frequency-domain acquisition.

## Syntax

    spectrum=overtone_dante(spin_system,parameters,H,R,K)


## Description

The function runs a DANTE pulse train followed by frequency-domain acquisition at the overtone frequency. Because time-domain overtone spectroscopy is difficult (see http://dx.doi.org/10.1039/C4CP03994G for details), this mode of acquisition is preferable in practice. Simulations assumptions should be set to 'qnmr'.

## Arguments

    parameters.sweep        -  vector with two elements giving the spectrum frequency extents
in Hz around the overtone frequency

parameters.npoints      -  number of points in the spectrum

parameters.rho0         -  initial state

parameters.coil         -  detection state

parameters.Lx           -  X Zeeman operator on the quadrupolar nucleus

parameters.pulse_dur    -  duration of each pulse, seconds

parameters.pulse_amp    -  amplitude of each pulse, Hz

parameters.pulse_num    -  number of pulses within rotor period

parameters.n_periods    -  number of rotor periods that the sequence is active for

H                       -  Hamiltonian commutation superoperator

R                       -  unthermalised relaxation superoperator

K                       -  chemical kinetics superoperator


## Returns

The function returns the populations of the detection state at the frequencies specified.

## Examples

See examples/nmr_overtone/dante_glycine.m example file.

## Notes

1. Relaxation must be present in the system dynamics, or the matrix inverse-times-vector operation performed by the frequency domain detection module would fail to converge. The relaxation superoperator should not be thermalised.
2. Relaxation theory is not applied during the DANTE sequence.