TOCSY

Set up appropriate 1H parameters. Normally should acquire 1D 1H spectrum first.

pw = 1H pulse, should be 90º pulse

tpwr = high power for 1H; should be set according to pw, or is correlated to pw.

nt = number of scans, should be multiple of 8, but 4 is acceptable

ni = number of t1 increments, points in t1 dimension, must be even number, preferably at least 128, 256 is preferable

np = number of points in t2 dimension, must be even number, 2048 is standard

slpw = spin lock pulse width, must be a 90º pulse with a pulse width of ~30-35 ms

slpwr = power of spin lock pulse, cannot be more than 49 units, preferably ~43 units, must correlate to slpw

mix = mixing time; the larger the mixing time the more transfers will occur (the more protons that will be correlated); generally 80-100 ms (so mix = .08 or mix = .1) is sufficient for ~5-8 transfers, 20 ms (mix = .02) is about right for ~1 strong transfer, one medium and one weak)

d1 = relaxation delay; normally should be slightly longer than in gCOSY, so 1.5 seconds is normal, but aromatic (or vinyl or methyl) protons usually need 2.0-2.5 seconds for optimal signal-to-noise


Steps:

1) Acquire 1 scan of 1H 1D experiment. Set cursors ~0.5 ppm beyond last proton resonance on both sides of spectrum, type command:
movesw

2) Re-acquire 1H 1D experiment (this is only required for 1H 1D on side of 2D spectrum)

3) Move parameters to another experiment. To move parameters from experiment 1 to experiment 3 type command:
mp(1,3)

4) Change to experiment 3, type command:
jexp3

5) Set TOCSY parameters with setup macro, type command:
TOCSY

6) Spin will likely turn off, if it does not, open Acqi window and manually turn it off. Lock Level should not drop more than ~5 %-10 %. If it does, you should reshim non-spin shims- X1, Y1, XZ, and YZ, and on higher field (500/600) X2Y2 and XY

7) Set the number of scans (nt) to appropriate value, generally 4 or 8 (it is preferable for nt to be a multiple of 8; nt might need to be increased for sufficient signal-to-noise, generally nt = 4 is sufficient if decent 1H spectrum
can be acquired in 128 scans), type:
nt=4

8) Set the number of points in t1 dimension (second dimension) (ni), generally 200-400 are suggested, type:
ni=256

9) Set d1 time, normally should be slightly longer than in gCOSY, so 1.5 seconds is normal, but aromatic (or vinyl or methyl) protons usually need 2.0-2.5 seconds for optimal signal-to-noise

10) Set the mixing time (parameter = mix); the larger the mixing time the more transfers will occur (the more protons that will be correlated); generally 80-100 ms (so mix = .08 or mix = .1) is sufficient for ~5-8 transfers, 20 ms (mix = .02) is about right for ~1 strong transfer, one medium and one weak)

11) Start acquisition, type command:
go

12) At end of experiment, set appropriate weighting functions and linear prediction parameters, type commands:
setLP1
sqcosine

13) If fn parameter now equals 4096, processing will be slow, then type:
fn = np
fn1 = fn

14) Process 2D type command:
wft2da

15) Switch f1 and f2 axes (make f2 the x-axis), type
trace = 'f2'

16) Display as contour plot, type command:
dpn10

17) If spectrum has yellow streaks and purple streaks horizontally across the spectrum, then the spectrum should be phased; set cursor on peak, type:
ds
then manually phase, be careful to only click once on spectrum during phasing, only rp (or rp1 phase correct should be changed)
redraw 2D type:
dpn10
If spectrum still has streaks in horizontal direction more phasing is required including lp (or lp1) phase correct. If spectrum has yellow/purple streaks in vertical direction, then the other dimension needs to be phased, so switch the axes, type:
trace = 'f1' (or 'f2'), depending upon which axis is currently the x-axis, then type:
dpn10

18) Spectrum should be appropriately referenced already, but you should confirm this; if necessary re-reference by putting cursor on appropriate diagonal peak and type (assuming CDCl3):
rl(7.26p)
rl1(7.26p)
dp10

19) Adjust vertical scale with vs +20% and vs -20% menu buttons or with middle mouse button or manually changing the parameter, vs2d, so vs2d = 100 (the lower the number, the less noise displayed), then redraw 2D with dp10 command

20) Print with 1D on side with 1D in experiment 1:
plcosy(10,1.2,1)

21) or Print with full rectangle, type:
full
dp10
pcon(10,1.2) page

22) Save data, type:
svf('filename')