It can be helpful to record a standard COSY experiment under identical conditions to ensure unambiguous assignments.

a 2D ¹H-¹H COSY-45 spectrum with rpar COSY45SW all , change the pulse program to cosyqfrl that

It is generally recommended that RELAY experiments be run without sample spinning.

The number of scans is determined as a function of the sample concentration (minimum phase cycle, ns 8 and ds 4).

The most important parameter to optimize is the fixed duration delay in the mixing step. As a general trend, d2 can be optimized to ca. 1/(3.2*J(HH)) (d2=52 ms for J(HH)=6 Hz).

(au_getlcosy)) (proc_2dsym).

Related 2D Multiple-steps RELAY experiments are also available (see Phase-cycle 2D experiments):

• Two-step RELAY experiment. Read the RELAY parameter set by typing rpar 'filename' all and change the pulse program to pulprog cosyqfr2. In this experiment, a second relay period (d3) is optimized as described for d2. All other acquisition and processing parameters as described before.
• Three-step RELAY experiment. Read the two-step RELAY parameter set by typing rpar 'filename' all and change the pulse program to pulprog cosyqfr3. In this experiment, a third relay period (d4) is optimized as described for d2 and d3. All other acquisition and processing parameters as described before.
• These experiments can also be recorded using incremented mixing time (see pulse programs cosyimqfr1 and cosyimqfr2).

Alternatively, the same information of all RELAY experiments can be extracted from 2D TOCSY experiments using different mixing times.