MK Page 1 of 13 Processing of Varian data MK,

MK Page 2 of 13 1D Phase Sensitive Experiment n Two points recorded per t 1 value, with a 90 o phase shift n The data are complex- FFT’ed, phase corrected, and the imaginary component discarded t1t1 {{{{{{ One real number The imaginary part - also a real

MK Page 3 of 13 2D Phase Sensitive Experiment n Each 1D slice is processed as a normal 1D spectrum The PPFIX command during processing of the first dimension removes the imaginary components (, ). A complex FFT is done in the second dimension (, ) t2t t1t1 { { { { {{{{{{

MK Page 4 of 13 3D Phase Sensitive Experiment - Bruker The PPFIX command during processing of the first dimension removes the imaginary components (,,,  ). A complex FFT is done in the second dimension (, ),(, ). The PPFIX in the 2nd dimension removes (, ) A complex FFT is done in the third dimension (, ) t3t t2t2 t1t { { { { { { { { { {{{{{{ {

MK Page 5 of 13 3D: Bruker vs Varian t3t3 t2t2 t1t1 0 1 { 0 { 1 { 0 { 1.. { 0 { 1 { 0 { { {{{{{{ t3t t2t2 t1t { { { { { { { { { {{{{{{ { { { { BrukerVarian { {

MK Page 6 of 13 3D: phase and phase t3t3 t2t2 t1t1 0 { 0 { 0 { {{{{{{ array=phase2,phase t3t3 t2t2 t1t1 0 1 { 0 { 1 { 0 { 1.. { 0 { 1 { 0 { { {{{{{{ { { { array=phase,phase { 1 { { 1 { 0 { 0 { { 1 { {

MK Page 7 of 13 3D: Sensitivity-enhanced spectra n In principle, two data sets are recorded. n They can be combined in two ways. The result is two sets of slices that differ by 90 o degrees n The second slice is subjected to a 90 o phase correction (equivalent to a Hilbert transformation) and added to the first slice n As the random noise in a spectrum and its Hilbert transform is statistically independent, adding the two slices above gives the well-known improvement by

MK Page 8 of 13 3D: grad_sort_nd t3t3 t2t2 t1t1 0 { 0 { 0 { {{{{{{ array=phase2,phase { 1 { 2 { 3 { 4 { 5.. { Add and subtract: Rearrange and rotate 90 o : grad_sort_nd2 swaps 2nd and 3rd slice before processing

MK Page 9 of 13 Processing in MNMR I n Download the experiment to an SGI machine n Look in the procpar file for the parameters: ni, ni2, and np n np no. of real points in t 3 n ni no. complex points in t 2 n ni2 no. complex points in t 1 n Size of FID file should be: 32+ni*2*ni2*2*(np*4+28) ni ni np

MK Page 10 of 13 Processing in MNMR II n Run grad_sort_nd, if necessary, on the SGI machine where you’ve moved the spectrum to. np:1024 ni:64 ni2:16 cd mv fid original_fid grad_sort_nd original_fid fid

MK Page 11 of 13 Processing in MNMR III n Processing in the t 3 dimension needs the parameters listed to the right: Use VARIAN 2 for phase2,phase and not sensitivity enhanced LOADTYPE 3 LOAD ZERO np SINESIZE np/2 SETEXP ni*2 ni2*2 VARIAN 1 FREQUENCY SWEEP 8000 PPFIX RR

MK Page 12 of 13 Processing in MNMR IV n Processing in the second dimension DIMENSION 1 FREQUENCY SWEEP 6000 ZERO ni*2 SINESIZE ni PPM PPFIX RR

MK Page 13 of 13 Processing in MNMR V n Processing in the third dimension - That’s it! DIMENSION 2 FREQUENCY SWEEP 2000 ZERO ni2*2 PPM NORMALIZE NOBC SINESIZE ni2