• Record a conventional ¹H spectrum using a 90 degree read pulse.

T1 ¹H measurements with rpar PROTONT1 all (the pulse program t1ir

Otherwhise, from the reference ¹H spectrum create a new dataset with edc or iexpno and change the pulse program to pulprog t1ir. All required parameters are as described for the ¹H spectrum. The inversion-recovery experiment is recorded as a 2D data set in which a delay (vd) is varied over the course of the experiment. For this reason, change parmod to 2D in eda. A 1D ¹H spectrum is obtained for each value of vd that can be readed using the corresponding rser command.

Define a vd-list by typing, for instance, edlist vd t1delay. Enter the desired delays (in seconds) as, for instance:

10s
5s
4s
3s
3s
2s
1s
0.5s
0.25s
0.1s
0.01s

and include it in the acquisition parameters by typing vdlist t1delay.

It is very important to use a long recycle delay, usually d1=5*T1(¹H) (d1=10 s), and l4=td1 is the number of experiments (or number of delays in vd-list).

(minimum number of scans ns=8 and ds=4).

The spectra can be processed by the automation program proc_t1 or manually entering xf2. In all cases, set SI1 as a power of two greater than or equal to the number of delays in vdlist (SI1=16). A linebroadening is usually applied (lb=1 Hz). More details in T₁ calculation.

It is advisable to store all acquisition and processing parameters (for instance, with the command wpar t1ir all) to be used later.

(au_zg)) (proc_2dt1).

The same experiment using a fix interpulse delay is also available (pulprog t1ir1d) to be used by the au-program invrec_au.

 Also see: ¹³C T₁ measurements using the Inversion-Recovery experiment