Unanswered questions
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J-Coupling In Proton NMR

1 1 7k
answers votes views
I'm currently a college student taking Organic Chem and I've no idea how to figure out the J-coupling for H-NMR and neit...
Posted: Scott 11 / Updated: Evgeny Fadeev 577●1 Aug 07 '10 at 11:37

Bruker Avance pulse sequences - where to find if not in TopSpin?

2 2 40665
answers votes views
I used to use Varian Inova systems with BioPack all the time, and now I'm using a Bruker Avance-III system geared for Ch...
Posted: jkurutz 131 / Updated: Charlie Fry 91 Aug 08 '10 at 09:34

How to create synthetic FID data in either Bruker, Varian or JEOL?

3 0 8k
answers votes views
Are there tools that allow to create raw data files in vendor format that contain desired data? For example for the tes...
Posted: Evgeny Fadeev 577●1 / Updated: John Hollerton 96 Aug 24 '10 at 06:55

Problem reading and transforming vendor data using C++/Qt

3 2 14187
answers votes views
Hi, I am a German chemistry Bachelor student (beginning my Master studies in October) and as a spare-time hobby I would...
Updated: Pascal Fricke 236 Aug 04 '10 at 00:16

How do you port pulse sequences to different field strength?

2 0 17113
answers votes views
Hi, when you set up a pulse sequence at a different magnet field strength - starting with an existing set of parameters ...
Posted: Evgeny Fadeev 577●1 / Updated: Kirk Marat 711 Aug 07 '10 at 09:07

What has been done with direct detection of Deuterium?

0 0 2k
answers votes views
Hello, I am trying to investigate what has been done in NMR using direct detection of deuterium in liquids. - Could you ...
Updated: Evgeny Fadeev 577●1 Jul 25 '10 at 14:49

What software can copy peak assignments for 2D T1 and T2 relaxation rate data analysis?

9 1 13274
answers votes views
Hello, I'm currently processing a large amount of T1 and T2 spectra in NMRDraw. I've been looking for a way to copy my ...
Posted: ccantr10 11 / Updated: Marcos 21 Sep 09 '10 at 10:09

When to label peptides and proteins and when not?

1 0 10015
answers votes views
When pursuing an NMR structure project - at what size of oligopeptide you would decide to label it with: 15N 13C both ...
Posted: Evgeny Fadeev 577●1 / Updated: Paul Driscoll 81 Feb 02 '11 at 04:28

what is importance of PH mode in topspin2.1

1 1 7k
answers votes views
hi,when i am processing nmr data in topspin 2.1,by default we are using pk mode in ph mode.there are other modes also su...
Posted: sashi 41 / Updated: Clemens Anklin 416 Jul 23 '10 at 21:21

What is your test for the feasibility of protein structure determination?

2 1 6k
answers votes views
How do you evaluate protein samples for the feasibility to solve 3D structure? For example if you record a test HSQC se...
Posted: Evgeny Fadeev 577●1 / Updated: Ilango 171 Jul 21 '10 at 12:35

benefits of higher field strength/ cryoprobe

1 1 17920
answers votes views
I'm working on a weak binding protein-peptide complex where the protein is labelled and the peptide is not. I can get sa...
Posted: nmr_novice 11 / Updated: Evgeny Fadeev 577●1 Jul 20 '10 at 11:31

what is standard procedure for importing data to topspin2.1

1 1 5k
answers votes views
hi,i am unable to import some nmr file which are stored in D or some other drives.. can anybody help me please thankyou ...
Posted: sashi 41 / Updated: Evgeny Fadeev 577●1 Jul 19 '10 at 13:25

how to import bruker data to felix

1 1 5k
answers votes views
hi,we have bruker(avance)-500Mhz nmr spectrometer ,topspin 2.0 is inbuilt software for this ,when i trasfer this data to...
Posted: sashi 41 / Updated: Evgeny Fadeev 577●1 Jul 18 '10 at 23:01

Aromatic shift or Hydrogen bond what are max and typical values

1 1 6k
answers votes views
I have studied several protein-protein interactions and often binding will result in very large proton shifts, I know al...
Posted: TomgA20 61 / Updated: Evgeny Fadeev 577●1 Jul 18 '10 at 10:12

Which Bruker HMBC program do you use?

7 2 11636
answers votes views
Hello, Here are Bruker hmbc pulse programs (produced by ls *hmbc*): hmbcacbigpl2ndqf hmbcacgplpqf hmbcetgpl2nd hm...
Posted: Evgeny Fadeev 577●1 / Updated: Arkadiusz Leniak 238 May 31 '14 at 15:21

Examples of protein degradation eg HSQC?

1 1 5k
answers votes views
Anyone know any websites or papers that show protein degradation in an HSQC for example? I wanted to know what to look ...
Posted: madge 11 / Updated: Evgeny Fadeev 577●1 Aug 08 '10 at 16:13

Will intermediate exchange give poor half filtered NOE

1 1 6k
answers votes views
I have recorded 2D half filtered NOE experiments on a protein-protein complex and got very poor quality data, why would ...
Posted: TomgA20 61 / Updated: Evgeny Fadeev 577●1 Jul 15 '10 at 08:17

Is there software to draw NMR pulse sequences?

1 1 9k
answers votes views
Hi, Is there a specific program to draw pulse sequences? (preferably in windows) ...
Posted: Cleber Barreto 73 / Updated: Evgeny Fadeev 577●1 Jul 10 '10 at 09:39

2D pulse sequences for NMR of protein/peptide complexes?

0 1 3k
answers votes views
Hello, I am looking for some 15N/13C-filtered 2D NOESY and 2D TOCSY pulse sequences to run on a Varian 600. Does anyone ...
Posted: acalab 21 / Updated: Evgeny Fadeev 577●1 Jul 26 '10 at 09:25

Looking for sample spectra....

2 1 6k
answers votes views
Hi guys : Is there a public database of sample Bruker/Varian NMR spectra ? I want to look at a sample 4D SER file ......
Posted: j 131 / Updated: Evgeny Fadeev 577●1 Jul 07 '10 at 14:41

How does pipe estimates Haight and DHeight?

4 1 5k
answers votes views
I`m new on Pipe. I was using the values from pipe to estimate R1 and R2. Because lots of signal in the HSQC were crowded...
Updated: Marcos 21 Jul 02 '10 at 10:55

What is the minimum information required to calculate a structure with cyana?

1 1 8k
answers votes views
Hi guys : I have several spectra, and wanted to test out what data I do , and do not need, in order to effectively get a...
Posted: j 131 / Updated: Bharathwaj 112 Jun 28 '10 at 19:43

Chemical shift and spin rate

2 1 5k
answers votes views
For solid state NMR: What can cause the line position shift depending on the spin rate? ...
Posted: KateSTR 11 / Updated: Evgeny Fadeev 577●1 Jun 21 '10 at 19:12

What does tcu error in bruker mean: ignored AQNEXT, busy FIFO is stopped?

1 0 10989
answers votes views
Has any one seen this type of error before? tcu error: Error in 'hsqcrexetf3gpsi3d.t22.d': line 92 (pc=50, ld=2300): - ...
Posted: Jeetender Chugh 31 / Updated: Ilango 171 Jul 09 '10 at 11:45

Why RF irradiation will damage amplifier?

3 1 17390
answers votes views
Here our 1H amplifier of NMR spectrometer is damaged twice for long time or high power RF irradiation. Why the duty cyc...
Posted: Frey 61 / Updated: lbeezley 1 Mar 15 '11 at 08:37

What is the origin of positive and negative coupling constants in NMR?

1 2 24316
answers votes views
When positive and negative coupling constants occur in NMR? and why? What are the spin states of the nuclei and the bond...
Posted: Ligia 21 / Updated: sekhar Talluri 621 Jun 13 '10 at 05:47

Can adamantane condense in a rotor of a solids probe?

1 0 5k
answers votes views
Hi, does anyone ever get adamantane from the rotor sublimate and condense outside it? A student here found a suspiciou...
Posted: Evgeny Fadeev 577●1 / Updated: Joseph DiVerdi 146 May 31 '10 at 06:25

How to make single page plots of arbitrary size in SPARKY?

0 0 3k
answers votes views
Hi, I need to plot a 2D spectrum so that it is 20cm wide (and tall) in sparky. Using pt command I can set up ppm/cm acc...
Updated: Evgeny Fadeev 577●1 May 27 '10 at 13:46

How to create synthetic procpar files for VNMRJ?

2 2 8k
answers votes views
Hi guys : Im trying to make a procpar for an FID, I know most of the parameters of importance, and have the schema of th...
Posted: j 131 / Updated: David Horita 31 Nov 09 '12 at 06:43

MODULE for RDC

2 1 6k
answers votes views
I'm trying to analyze my RDC data using Module. But I'm using a crystal structure instead of NMR. Can somebody pls advis...
Posted: shub 31 / Updated: Evgeny Fadeev 577●1 Jul 28 '10 at 11:09

BRUKER Fid data ordering

2 2 17193
answers votes views
Hi guys : This post is related to : qa.nmrwiki.org/question/83/where-to-find-technical-information-on-varian-and-bruke...
Updated: j 131 May 25 '10 at 11:45

Eliminating NOE restraints

1 1 6k
answers votes views
I have collected over 370 NOE restraints for a 38 AA peptide. Because I have less than 10 restraints per residue, I am ...
Posted: E V Clarke 11 / Updated: sekhar Talluri 621 May 23 '10 at 12:18

How to reference indirect dimensions in Topspin?

0 1 5k
answers votes views
Hello, When I process 3d data on topspin with the ft3d command, I get the three-dimensional spectra, but the chemical sh...
Posted: Gili 11 / Updated: Evgeny Fadeev 577●1 Jul 26 '10 at 09:24

How to configure vnmr to save postscript files

1 0 6k
answers votes views
Hello, I know I've done this before but did not write the details down. How to make vnmr save postscript files? Normall...
Posted: Evgeny Fadeev 577●1 / Updated: Gareth Morris 71 May 13 '10 at 01:28

How to remove baseline DC offset in Bruker EMX EPR spectra?

1 0 5k
answers votes views
Hello, I've noticed recently that our EPR spectrometer (Bruker EMX500) has a negative offset on the baseline and it bec...
Posted: Evgeny Fadeev 577●1 / Updated: Alex Blumenfeld 11 May 12 '10 at 11:55

Why chiral(-*C-)centre attached Ethylene(-CH2-)group splits into two separate protons(or)peaks ?

1 1 5k
answers votes views
About chiral centre ...
Posted: RAM 21 / Updated: Evgeny Fadeev 577●1 May 01 '10 at 17:48

How to determine E vz Z olefin isomer when proton resonances orverlap?

3 1 17140
answers votes views
We have an olefin, R1-CH=CH-R2 where proton resonances overlap. Is there a way to determine olefin isomer - E (trans) vs...
Posted: Evgeny Fadeev 577●1 / Updated: Cleber Barreto 73 Jul 10 '10 at 08:07

How to best correlate Deuterium with other nuclei by NMR?

2 0 6k
answers votes views
Hello, I've been asked to solve a problem of assigning a positon of deuteration on a molecule, where structure of the de...
Posted: Evgeny Fadeev 577●1 / Updated: kiscs kiscs 21 May 17 '10 at 16:43

Limit Testing by NMR?

3 1 10419
answers votes views
Is it possible to use NMR for limit testing of trace impurities in pharmaceutical drug substances? What are the conside...
Posted: Chris Kirchner 11 / Updated: sekhar Talluri 621 May 23 '10 at 11:49

How to assign (perturbed) resonances when structure is known?

1 0 6k
answers votes views
I had two problems like this one recently: have protein (in solution) of known general structure resonance assignments...
Posted: Evgeny Fadeev 577●1 / Updated: Aleksandr Yakimov 11 Apr 25 '10 at 01:17

How to confirm structure of propane by NMR?

2 2 5k
answers votes views
I will really need your help. I am chemist working in the oil buisness and I am interesting is it possible to analyze pr...
Posted: Silvija 21 / Updated: ron daedalus 11 Apr 21 '10 at 09:18

Why are my acetic acid-d4 solvent peaks off from the expected ppm value?

1 1 9k
answers votes views
Hello there. After running an 1H-NMR experiment I observed the acetic acid-d4 solvent peaks at 11.54 and 21.16 ppm (off...
Posted: BONA 11 / Updated: Evgeny Fadeev 577●1 Apr 12 '10 at 15:08

How to determine the conformation of cis-cyclohexyl derivative by NMR?

1 1 5k
answers votes views
This cis-cyclohexyl derivative with two big substitutes (A and B) may has two conformational isomers, 1 and 2. How to ...
Posted: Jack 31 / Updated: Evgeny Fadeev 577●1 Apr 05 '10 at 12:36

How to set up Gaussian pulse to satisfy desired bandwidth?

1 1 12489
answers votes views
Hello, posting this on behalf of my friend. The goal is to set up a gaussian shaped pulse so that bandwidth is X Hertz...
Updated: Evgeny Fadeev 577●1 Apr 02 '10 at 13:15

For the RDC analysis - how to tell when the sample is acceptable/useful?

4 1 17110
answers votes views
I have a rather simple question - What is the acceptable difference in coupling constants between the anisotropic and is...
Posted: shub 31 / Updated: Bharathwaj 112 Jun 22 '10 at 07:16

Are there ways to explain magnetic-field dependent chemical shift?

4 1 26971
answers votes views
Hi everyone, I was wondering whether anyone could help me to explain why the chemical shifts in my proton and carbon NM...
Posted: Guga Hollows 11 / Updated: Arkadiusz Leniak 238 May 31 '14 at 15:46

How to open multiple pdb files with PyMol - all at once?

3 0 27292
answers votes views
Hello, I've started using PyMol for looking at the bundles of NMR structures. You can open files one-by-one, but it's ki...
Posted: Evgeny Fadeev 577●1 / Updated: dummy2 1 Apr 05 '13 at 07:03

Is there a tool to manage NOE and other restraint lists for the structure calculations?

1 0 5k
answers votes views
Hello, I'm currently working on solving a peptide NMR solution structure using NIH-XPLOR. I find myself a lot starting ...
Posted: Evgeny Fadeev 577●1 / Updated: Ilango 171 Apr 02 '10 at 05:45

Software to model a 9-mer peptide that binds divalent metals and may oligomerize?

1 1 12014
answers votes views
I'm gearing up for a project in which we're looking at the structure of a short peptide that should fold upon binding di...
Posted: jkurutz 131 / Updated: Evgeny Fadeev 577●1 Mar 18 '10 at 09:32

Is there a way to measure scalar coupling when lines are broad?

1 1 5k
answers votes views
Hello, we have a peptide where amide peaks are broad and there is no hint of observable coupling with HA protons (no dis...
Posted: Evgeny Fadeev 577●1 / Updated: jkurutz 131 Mar 16 '10 at 14:59
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