Please use only intact sample tubes and check if the fit and condition of the plug are correct.

 

Sample tubes must not be longer than 21 cm and not shorter than 15 cm.

 

Sample tubes should be marked in the upper quarter with the sample id identical with the id given on the submission form (permanent marker).

 

Please observe the requested amount of deuterated solvent (4.5 cm, 700ul).

 

Please submit your samples with a reasonable and appropriate concentration.

 

Your samples should be homogeneous (no suspension, no precipitate) and diamagnetic.

 

Please choose the machine which suites your requirements best.

 

Keep appointments and submit samples for overnight measurements by 2:00 pm (Friday 11am)

 

Please fill out the form thoroughly, completely and unambiguously. Please mention in particular if your solvent is only partially or not deuterated

 

 

Please use only intact sample tubes and check if the fit and condition of the plug are correct.

In order to improve the homogeneity we have to shake the samples before starting the measurement. In addition we cannot insure that during the handling the sample is always in an upright position. Thus in case of a broken sample tube your substance might get spilled.

 

Sample tubes must not be longer than 21 cm and not shorter than 15 cm.  

Sample tubes which exceed a length of 21cm will be broken by the sample changer. On the other hand, a length of 15 cm is necessary in order to be able to place the sample in between the r.f. coils of the probe head.  

 

Sample tubes should be marked in the upper quarter with the sample id identical with the id given on the submission form (permanent marker).

In case of a wrong labelling we might not be able to return you your proper sample. Because we are handling many samples at the same time (sample changer), they might get mixed up.  

 

Please observe the requested amount of deuterated solvent (4.5 cm, 700ul)

We have to spend a lot of time to achieve a good homogeneity of the local magnetic field. For this reason we need a minimum amount of deuterated solvent. If your tubes are not properly filled you might obtain broad signals or observe a splitting of peaks. Please shake the sample thoroughly before submission. There can be regions of different concentration in the sample spoiling the homogeneity as well. Because only the small volume in between the r.f. coils can be observed, too much solvent only causes a dilution of your sample.

 

Please submit your samples with a reasonable and appropriate concentration.

Samples have to be submitted with a concentration, which is suited for the required experiment (e.g. 50 to 100 mg, 13C, medium sized compound). For the acquisition of routine carbon 13 spectra we can’t afford more than 128 scans (10 min real measurement time). The signal to noise ratio increases only with the square root of the measurement time. For this reason a useful carbon 13 spectrum could hardly be obtained after half an hour if it does not displays a clear signal after 10 minutes. If the available amount of substance is only small you should use only as much deuterated solvent as necessary (see above). If you can not get a meaningful carbon 13 spectrum, we can offer you an overnight measurement. You can switch to HMQC/HMBC spectra as well, which are much easier to obtain (higher sensitivity).

 

Your samples should be homogeneous (no suspension, no precipitate) and diamagnetic.

Not dissolved substance, ferromagnetic and paramagnetic material can spoil your spectra.

 

Please choose the machine which suites your requirements best:

       Spectrometer                      best suited for                                 server                       partition           .  

        

             AC250         1H 13C concentrated sample only, overnight 13C            nmr.chemie….       /u/data/ASPECT/nmr 

                    

             ECX400      1H 13C DEPT 19F 31P (only ECX)                                  chemnet                 /a/data/ecx/nmr (delta)

 

             AMX500     13C DEPT                                                                          chemnet                 /a/data/ecp/nmr (delta)

 

             ECP500       1H 2D COSY HMQC HMBC                                            chemnet                /a/data/amx/nmr (delta)

 

Data are available in the XWINNMR format (/nmr) or Jeol Delta format (/delta).

Spectra obtained at different field strengths can be used in combination (e.g. HMQC, C)

If a 13C spectrum of a certain sample has been measured already recently at 400 MHZ, please mention the filename when submitting the sample for a HMQC experiment.

 

Keep appointments and submit samples for overnight runs until 2 pm (11 am Friday).

We are short of measurement time. Any free time overnight may be needed by somebody else.

 

Please fill out the form thoroughly, completely and unambiguously. Please mention in particular if your solvent is only partially or not deuterated.

The information about your sample is needed for carrying out the required experiment. The knowledge of the solvent you have used is very important in particular when working with sample changers. A trial structure of your molecule would help us to pay attention to special carbons. The amount of material can give us an idea how much measurement time might be needed. Please submit each sample with one form (AC2500 at most 3 samples), otherwise they could get mixed up. For 250 MHz spectra please give us your filename and sufficient numbers. 400 and 500 MHz data will be saved using your name together with some extensions. As students can not get an account on their own they will need a signature and an account to save the data. A word document of the submission form can be found at: /a/data/backup/Spektrenzettel.latest version.doc