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Basic Spectrometer Data

BRUKER

MAGNETIC FIELD [TESLA]

1H-FREQUENCY [MHz]

PROBEHEADS

LOCATION

AVANCE III HD
300 GA

7.05

300.13

5mm ATM BBfO
1H, 13C, 31P, 11B, 19F
1D Experiments  

DCB

AVANCE II
400 GB

9.395

400.13

5mm ATM Dual
1D & 2D
1H / 13C experiments

DCB

AVANCE III HD
300 GC

7.05

300.13

5mm ATM BBfO
1H, 13C, 31P, 11B, 19F
1D Experiments  

DCB

AVANCE III HD
400 IOCSP1

9.395

400.13

5mm ATM  BBfO SmartProbe
1D & 2D all nuclei
5mm ATM BBI

DCB

AVANCE II
500 IOCSP2

11.75

500.13

1.7mm TXI 1H, 13C, 31P
5mm Diffusion (research)

DCB

AVANCE II
500

11.75

500.13

4 mm 1H & 13C HR-MAS

Insel

 

Acquisition and Processing Parameters

The acquisitions and processing parameters are located in the following files (valid for all Bruker data):

Acquisition data:
<home_directory>/<name_of_file>/<number_of _exp/acqus
(for instance: /nmr/cyclosporine/1/acqus)

Processing data (integrals, peak picking,..)
<home_directory>/<name_of_file>/<number_of _exp/pdata/1/procs
 (for instance: /nmr/cyclosporine/1/pdata/1/acqus)

 

Helium Level

(Access restricted to the NMR Group members)

Standard Experiments

O: original reference; V: references of later experimental variants

13C-APT (attached proton test)

Determines 13C chemical shifts and differentiates between Cq, CH, CH2, CH3 groups (positive/negative signals)

O: S. Patt, J.N. Shoolery, J. Magn. Reson. 46, 535-539 1982  

 

13C-DEPT (distorsionless enhancement by polarization transfer)

Determines 13C chemical shifts and differentiates between CH, CH2, CH3 groups (positive/negative signals). 

The signals of Cq and solvent signals are suppressed.

O: M.R. Bendall, D.M. Doddrell, D.T. Pegg, J. Am. Chem. Soc. 103, 4603-4605 1981

 

13C-DEPTQ (distorsionless enhancement by polarization transfer including quaternary carbons)

Determines 13C chemical shifts and differentiates between CH, CH2, CH3 and Cq groups (positive/negative signals).

O: R. Burger, P. Bigler, J. Magn. Reson. 135, 529-534 1998 DOI: 10.1006/jmre.1998.1595
V: P. Bigler, R. Kümmerle, W. Bermel, Magn. Reson. Chem. 45, 469-472 2007 DOI: 10.1002/mrc.1993
P. Bigler, Spectroscopy Letters 41, 162-165 2008 DOI: 10.1080/00387010802008005

Note:
The edited DEPTQ spectra with Cq/CH signals in one and CH2/CH3 signals in the other are stored as follows:

subspectrum with Cq/CH

500

subspectrum with CH2/CH3

501


 

1H{1H}-NOE (nuclear Overhauser enhancement)

NOEs take advantage of direct (dipolar) spin-spin couplings and allow to detect and measure intra- and intermolecular spatial proximity among protons.
O: D. Neuhaus, M. Williamson, The Nuclear Overhauser Effect, VCH, Weinheim 1989

Note:
So-called steady-state NOEs are measured, in contrast to the inherently weaker transient effects obtained with 2D techniques, such as NOESY and ROESY

For small molecules NOEs are positive (with a maximum of +0.5); for large (bio-) molecules NOEs are negative (with a maximum of –1.0) but spin diffusion occurs and complicates the interpretation.

Difference spectra are calculated which allow even weak NOEs to be recognized most conveniently

Reference spectrum and NOE-difference spectra are calculated automatically and are stored under the same filename but with different extensions (experimental numbers or “expnos” ):

 

 

example

original spectrum

expno  

12

reference spectrum

expnoref = expno x 100 + 10000

11200

 

NOE-difference spectrum 1

expnodiff = expnoref +100

11300

NOE-difference spectrum 2

expnodiff = expnoref +101

11301

NOE-difference spectrum 3

expnodiff = expnoref +102

11302


 

1H/1H-COSY (correlation spectroscopy)

Detects homonuclear coupling interactions (indirect coupling) among protons of a molecule and allows coupling (J-connectivity) networks to be established most efficiently.

O: W.P. Aue, E. Bartholdi, R.R. Ernst, J. Chem. Phys. 64, 2229-2246 1976 DOI: 10.1063/1.432450
V: R.E. Hurd, J. Magn. Reson. 87, 422-428 1990
A. Derome, Williamson, J. Magn. Reson. 88, 177 - 185 1990  (MQ-filtered, phaseable version)

 

1H/1H-NOESY (NOE correlation spectroscopy)

Detects intra- and intermolecular spatial proximity (via direct coupling) among protons and allows to establish the corresponding dipolar network most efficiently. The same experiment (EXCSY) may be used to detect chemical and dynamic exchange among protons.

O: J. Jeener, B.H. Meier, P. Bachmann, R.R. Ernst, J. Chem. Phys. 71, 4546-4563 1979 DOI: 10.1063/1.438208
V: D.J. States, R.A. Haberkorn, D.J. Ruben, J. Magn. Reson. 48, 286-292 1982  

Note:
NOEs are dependent on molecular size and tumbling rates characterized by correlation times. For small molecules NOEs are positive (with a maximum of +0.385); for large (bio-)molecules NOEs are negative (with a maximum of –1.0). 

For molecules of intermediate size NOEs may be close to zero even for closely spaced protons. The ROESY experiment is used in such situations.

So-called transient NOEs are measured, in contrast to the stronger steady-state NOEs obtained with the 1D NOE experiment.  

 

1H/1H-ROESY (ROE correlation spectroscopy)

Detects intra- and intermolecular spatial proximity (via direct coupling) among protons and allows to establish the corresponding dipolar network most efficiently. The same experiment (EXCSY) may be used to detect chemical and dynamic exchange among protons.

O: A.A.Bothner-By, R.L. Stephens, J.-M. Lee, C.D. Warren, R.W.Jeanloz, J. Am. Chem. Soc. 106, 811-813 1984 DOI: 10.1021/ja00315a069
A. Bax, D.G. Davis, J. Magn. Reson. 63, 207-213 1985

Note:
In contrast to the NOESY experiment with the NOE built up under the influence of the strong static magnetic field, ROEs are built up in the much weaker “rotating field”. 

As a consequence ROEs are positive throughout (no zero-crossing) irrespective of the molecular size, but yield weaker effects for large molecules (<0.7 compared to –1.0 for NOEs)

So-called transient ROEs are measured, in contrast to the stronger steady-state NOEs obtained with the 1D NOE experiment.  

 

13C/1H-HSQC (Heteronuclear single quantum correlation spectroscopy)

Detects heteronuclear coupling interactions (indirect coupling) between protons and directly bound carbons (1JCH) of a molecule and allows coupling (1JCH-connectivity) networks to be established most efficiently.

O: G. Bodenhausen, D.J. Ruben, Chem. Phys. Lett. 69, 185-188 1980 DOI: 10.1016/0009-2614(80)80041-8
V: L.E. Kay, P. Keifer, T. Saarinen, J. Am. Chem. Soc. 114, 10663-10665 1992 (gradient selected version) DOI: 10.1021/ja00052a088
W. Willker, D. Leibfritz, R. Kerssebaum, W. Bermel, Magn. Reson. Chem. 31, 287-292 1993
J. Schleucher et al. J. Biomol. NMR 4, 301-306 1994 DOI: 10.1007/BF00175254

Note:
13C chemical shifts are detected indirectly by taking advantage of single quantum t1-evolution

 

13C/1H-HMQC (Heteronuclear multiple quantum correlation spectroscopy)

Detects heteronuclear coupling interactions (indirect coupling) between protons and directly bound carbons (1JCH) of a molecule and allows coupling (1JCH-connectivity) networks to be established most efficiently. 

O: L. Müller, J. Am. Chem. Soc. 101, 4481-4484 1979 DOI: 10.1021/ja00510a007
V: A. Bax, S. Subramanian, J. Magn. Reson. 67, 565-569 1986
R.E. Hurd, B.K. John, J. Magn. Reson. 91, 648-653 1991 (gradient selected version)

Note:
13C chemical shifts are detected indirectly by taking advantage of multiple quantum t1-evolution.  

 

13C/1H-HMBC (Heteronuclear multiple bond correlation spectroscopy)

Detects heteronuclear coupling interactions (indirect coupling) between protons and remote carbons (mainly 2JCH, 3JCH) of a molecule and allows “long-range” coupling networks to be established most efficiently.

O: A. Bax, M.F. Summers, J. Am. Chem. Soc. 108, 2093-2094 1986 (gradient selected version) DOI: 10.1021/ja00268a061
V: D.O. Cicero, G. Barbato, R. Bazzo, J. Magn. Reson. 148, 209-213 2001 (F1 phased version) DOI: 10.1006/jmre.2000.2234

Note:
in contrast to HSQC, HMQC heteronuclear “long-range” connectivities include also quaternary carbons.   

 

13C/1H-HMSC (Heteronuclear multiple and single bond correlation spectroscopy)

Detects heteronuclear coupling interactions (indirect coupling) through one (1JCH)  and more (2JCH, 3JCH) bonds 

simultaneously. The two types of connectivities are disentangled and the corresponding two spectra are calculated automatically.

O: R. Burger, C. Schorn, P. Bigler, J. Magn. Reson.148 (1), 88-94 2001 DOI: 10.1006/jmre.2000.2223

Note:
The two spectra with the 1JCH- and the 2JCH/3JCH- connectivities will be stored with “expnos” 900 and 902 respectively

The spectra are measured without 13C broadband decoupling. As a consequence doublets (spitted by 1JCH) are obtained in the 1JCH subspectrum.

 

19F

Note:
Since the internal calibration of our NMR spectrometers is very accurate (<0.05 ppm) and stable (using the lock signal), no additional 19F spectrum of 80% CFCl3  in CDCl3 will be provided anymore

 

31P

Note:
Since the internal calibration of our NMR spectrometers is very accurate (<0.05 ppm) and stable (using the lock signal), no additional 31P spectrum of 85% H3PO4 in H2O will be provided anymore.