Cheers -Kirkĭear Kirk, it looks like you prefer Bruker instruments! You know that the purpose of the blog is not to assess which spectrometer is better, but such a discussion would be accepted nonetheless. It would have been a lot easier if they had numbered the dimensions the other way around! :-) With the acquisition period always being t1, the first indirect evolution time as t2 (2D NMR) the next indirect evolution time as t3 (3D NMR) etc. sw2 is not the width if F2 but is the width in the second indirect dimension. For example sw is always the spectral width in the direct dimension. The same sort if inconsistency exists with Varian parameters as well. Now the files even report a meaningful value for the temperature! However, the parameter editors eda, edp, (which is what the user sees) correctly refer to the directs dimension as F2 (for 2D) for F3 (for 3D) and the documentation refers to it this way as well. This is so you can add another dimension without changing the name of an existing file. Yes, the files are called acqus, for direct dimension and acqus2 for the first indirect dimension, etc. I agree that it used to be worse in the past. The Bruker software that I know stores the f2 parameters into a file called acqus and the f1 parameters into a file called acqu2s. For truly dreadful, awful 2D NMR phasing try VNMRJ The Bruker Software and documantation that I have correctly refers to the direct dimension as f2 and the indirect one as f1. Being this in contrast with the definition, the theorem is demonstrated. > Bruker calls "f2" the indirect dimension and "f1" the direct one. Each time you feel having reached the perfect correction, increase the amplitude factor (= press the plus key). To become a wizard in phase correction, make practice with good-looking, good-behaving spectra. Learn the iNMR mechanism "Extract"-"Repeat" and use it to find the right FT parameters. If you know that a spectrum is phase-sensitive or "echo-antiecho", use the corresponding shuffling along the indirect dimension, but never along the direct one. When you have found the right phase parameters, you can add zero-filling or LP-filling. If you have troubles with the phase correction, use a sine bell shifted by 90 degrees along f2 and a squared sine bell shifted by 90 degrees along f1, and do not use neither LP-filling nor zero-filling. The only exception I remember is represented by Bruker spectra in pure "TPPI" mode, which require "Real FT" only along f1. The only exception I remember is represented by Bruker spectra in "States-TPPI" mode, which require "swap sides" only along f2. In such case, ignore outlier peaks and phase the rest. When the pulse sequence become longer, and if you add a pre-saturation step, phasing all peaks may become impossible. With the classic NOESY, TOCSY and ROESY experiments it is possible to bring in phase all signal simultaneously. If you get the correct number of peaks in the correct chemical shift order, your parameters are correct. If your FT parameters are wrong, you get all the signals doubled, or they fall at the wrong chemical shift, or both things happen. First thing first: you should determine if yours is a problem of phase or a poor choice of FT parameters. Demonstration of the corollary is left to the reader as an exercise. The dimension with the highest index is called "direct", all others being "indirect".īruker calls "f2" the indirect dimension and "f1" the direct one. It is necessary, therefore, to learn some theory. Non-academic users of our facility must provide for their own processing software licenses.Processing a 2D spectrum can sometime become a puzzle. We provide licenses for MNova, Rxn Monitoring and QNMR only, and only to academic users. Many of the marketing and help guides on the MestreLab website discuss other plug-ins. Licenses for MestreLab’s Reaction Monitoring and QNMR plug-ins are available on the installation page. MestreLab’s NMRPredict and Verify plug-ins are installed on three PCs in the NMR labs (mordor, vir, horton). Replace old licenses from our installation page. If your license has timed out, reconnect to the campus network via VPN and restart MNova. Please do not contact MestreLab about license issues. Researchers should contact NMR staff, and all undergrads contact the OrgLab staff, for questions and issues. The Facility has a campus site license for MestreLab’s MNova software. Bruker’s TopSpin processing software is now free for academic users at Bruker’s website.
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