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Useful stuff, tips & tricks (VnmrJ software, Linux)

Pulse Sequences:
Double (H,C) band-selective bsEXSIDE
CPMG-HSQMBC
COLOC-S

Interface:
Improved "More 1D" and "More 2D" panels

Linux tips & tricks
setting up a SAMBA server
top command


Double (H,C) band-selective bsEXSIDE pulse sequence

One problem of the standard, default EXSIDE pulse sequence (which is used to measure nJCH coupling constants) is its long measurement time, as a very high resolution is required in F1 to adequately measure the small couplings (typically ni > 600). At the same time, only very few coupling can be measured simultaneously (by exciting multiple protons), as these protons may not be mutually coupled by JHH couplings.
To alleviate this, a bsEXSIDE was created that adds a band-selectivity in F1, thus dramatically reducing the number of increments required. Typically only a single nJCH is measured with this experiment.

Original paper: SelEXSIDE: fast and easy measurement of multiple-bond 1H,13C coupling constants for stereochemical analysis

The attached package is an appdir and contains pulse sequence, parameters, Chempack/VnmrJ3+ compatible panels, setup macros and an Experiment Selector button.

Installation: copy the file anywhere and unpack with
      tar zxf bsEXSIDE.tgz
Then activate the resulting bsEXSIDE directory as an appdir under Edit → Applications.

Download bsEXSIDE.tgz

CPMG-HSQMBC pulse sequence

This is an HSQMBC pulse sequence to measure long-range nJCH coupling constants.

Original paper: One- and two-dimensional gradient-selected HSQMBC NMR experiments for the efficient analysis of long-range heteronuclear coupling constants

The attached package is an appdir and contains pulse sequence, parameters, Chempack/VnmrJ3+ compatible panels, setup macros and an Experiment Selector button.

Installation: copy the file anywhere and unpack with
      tar zxf CPMGHSQMBC.tgz
Then activate the resulting CPMGHSQMBC directory as an appdir under Edit → Applications.

Download CPMGHSQMBC.tgz

COLOC-S pulse sequence

This is a 13C detected COLOC-S experiment that is considerably old but can still have its uses:
When running in undecoupled fashion, one can use it to determine long-range CH coupling constants for signals that otherwise would overlap in the 1H dimension (EXSIDE/bsEXSIDE or HSQMBC may not help here if overlap is too bad). With the resolving power of 13C this may be one way out (albeit it's a very unsensitive experiment of course). The minimum phase cycle of this slightly modified version is 4 (original paper: 16).

Original paper: COLOC-S: A modified COLOC sequence for selective long-range X-H correlation 2D NMR spectroscopy

The attached package is an appdir and contains pulse sequence, parameters, Chempack/VnmrJ3+ compatible panels, setup macros and an Experiment Selector button.

Installation: copy the file anywhere and unpack with
      tar zxf COLOC.tgz
Then activate the resulting COLOC directory as an appdir under Edit → Applications.

Download COLOC.tgz


Improved "More 1D" and "More 2D" panels (easier solvent subtraction)

These panels (Chempack/VnmrJ3+ compatible) provide the following additions:
  • 1D: choice between Hz & ppm for solvent subtraction
  • 2D: choice between solvent subtraction in F2 and F1 (will create missing parameters)
  • 2D: choice between Hz & ppm for solvent subtraction
  • 2D: "set" button like for 1Ds

Installation: copy the file into your local vnmrsys directory and unpack with
      tar zxf More1D2D.tgz
Restart VnmrJ.

Download More1D2D.tgz