Unanswered questions

Help for Boron 11 NMR!

10 1 16148
answers votes views
I'm using a Bruker 300 NMR, equipped with a BBO probe, to do Boron 11 NMR. But I got no signal no matter what pulse leng...
Posted: Chemuri 11 / Updated: Jim Lin 1 Apr 14 '15 at 06:47

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

9 1 11750
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

distorted DOSY ID

9 1 8k
answers votes views
Why are some Dosy spectra 1d so distorted (like the one below)?. How can this be overcome? ...
Posted: @ 11 / Updated: Umayal Rakesh 1 Mar 30 '15 at 00:08

Which Bruker HMBC program do you use?

7 2 10465
answers votes views
Hello, Here are Bruker hmbc pulse programs (produced by ls *hmbc*): hmbcacbigpl2ndqf hmbcacgplpqf hmbcetgpl2nd hm...
Posted: Evgeny Fadeev 5771 / Updated: Arkadiusz Leniak 238 May 31 '14 at 15:21

What will happen if I use long pulse?

7 1 11246
answers votes views
Hello everybody. We have an AVANCE 500 MHz bruker instrument. Unfortunately, our amplifier has been weakened and I can n...
Posted: He 21 / Updated: jkurutz 131 Jul 19 '12 at 06:24

Tool to extract NMR data in XY text file format?

6 0 20739
answers votes views
I need to give NMR data to someone who has only spreadsheet software to prepare plots of data and she also wants to fit ...
Posted: Evgeny Fadeev 5771 / Updated: Michael 1 Aug 19 '14 at 05:17

Why is chemical shift range of 13C wider than of 1H nuclei?

6 3 19261
answers votes views
Why the chemical shift range of 1H nmr is ~20 ppm wheras for 13C nmr it is ~230 ppm? ...
Posted: sameer deka 31 / Updated: Yoan Monneau 136 Feb 15 '11 at 11:23

peptide protein interaction

6 1 9k
answers votes views
I have determined the structure of a 110 residues protein(11kDa) which is known to interact with a 15mer peptide. Now I ...
Posted: man05 11 / Updated: Justin Frank 1 Jun 27 '16 at 22:44

Bruker DRU ADC-overflow warning message in Topspin during HSQCEDETGP

6 1 18203
answers votes views
To experienced Bruker users: I often get the following message in ICON-NMR while running HSQC/HMQC: "zg: DRU warning: n ...
Posted: Sylvain Demanze 71 / Updated: djh 1 Aug 11 '11 at 02:49

assignment of 12 kd protein

6 1 7k
answers votes views
Dear NMR Wikiers ! I encountering problem with assignment of 12 kd protein ! i assigend already 50 percent of backbone ...
Posted: sri 71 / Updated: Thomas Garner 81 Aug 30 '11 at 07:11

topshim giving worse lineshape

6 0 13798
answers votes views
HI ON bruker av-500 topshim giving worse line shape spectra for e.g it is getting the right keys but in wrong direction...
Posted: feroon 21 / Updated: John Hollerton 96 Jan 23 '13 at 02:57

Very simple NMR question wrt resonance frequency calculation

6 0 20822
answers votes views
Hi guys, I'm stuck in attempting this question and need some help understanding how to answer it. Q.) The chemical shif...
Posted: Will Whitehouse 1 / Updated: SankarampadiAravamudhan 91 Apr 02 '14 at 00:25

3DNMR CBCANH experment

5 1 8k
answers votes views
Dear NMR wiki ers Iam working on protein family which can form dimers (total 20kd size ) using 25mM TRIS , 100 mM KCL...
Updated: sri 71 Aug 25 '11 at 00:09

Line broadening in nmr

5 0 8k
answers votes views
Hello can some body help me in understanding the line broadening effect in NMR? I am working with protein and small mol...
Posted: fatima A 1 / Updated: Evgeny Fadeev 5771 Oct 12 '11 at 07:25

Method for indirect 13C-1H J-couplings measurements

5 1 7k
answers votes views
Dear colleagues! 13C-1H J-couplings are essential in some areas of molecule structure research. I discovered modern met...
Updated: VVK 61 Nov 29 '11 at 12:37

capacity to run 19F13C NMR exp.

5 0 4k
answers votes views
Hi all:) I apologize for my simple ( or well, stupid) question: I was wondering if it is possible to run a 2D 13C19F exp...
Posted: Ala M. 1 / Updated: VVK 61 Nov 27 '12 at 12:24

MAS spin counting

5 0 3k
answers votes views
Hi, We have a Bruker MAS probe (4mm, late 90s vintage, widebore) that reports a spin speed twice what it is actually doi...
Posted: Kate Nairn 11 / Updated: w101bdk 7 Nov 13 '13 at 10:22

selective noesy

5 0 4k
answers votes views
Hi, I have question for you who have Bruker instruments! On 300 MHz I worked on selective noesy pulse sequence (selnogp)...
Posted: gugica 1 / Updated: Pete Gierth 401 Feb 13 '14 at 14:58

Which Bruker HSQC program do you use?

5 0 9k
answers votes views
Hello, could you tell me which HSQC and E-HSQC program are recommendable ? These are Bruker HSQC pulse programs: hsqcp...
Posted: lithiumamide 1 / Updated: RuudA 11 Sep 10 '14 at 11:46

Distorted/antiphase signals when doing Dosy

5 0 3k
answers votes views
Hello, I am running Dosy experiment using ledbpgp2s sequence. I am getting sort of signal distortions. I tried the solu...
Posted: Umayal Rakesh 1 / Updated: gravatar 83 Jun 08 '15 at 03:44

Weak NOE signals, serious t1 noise

5 0 6k
answers votes views
Since my university does not have a professional spectroscopist, I am a new learner of NMR, and I really have no one els...
Posted: Elvis 1 / Updated: RuudA 11 Nov 02 '14 at 07:22

1H-31P Hetcore with Varian inova 500, How can it be possible?

4 2 8k
answers votes views
I use a varian inova 500 NMR machine. it has vnmrj 2.1B software. An auto-x pfg 500 Mhz probe and auto tuning unit also....
Posted: oksijen 26 / Updated: Ulrich Haunz 210 Apr 27 '10 at 00:34

Software to calculate chemical exchange lineshape

4 2 9k
answers votes views
Are there any modern programs (preferably freeware) that will simulate line broadening in the presence of exchange. Some...
Posted: dstephenson 56 / Updated: Jana 31 Apr 19 '13 at 21:47

14N solid state NMR

4 1 6k
answers votes views
I would like to run some solid state 14N NMR spectra, but I have never run experiment on integer spins in the solid stat...
Posted: Anne Baudouin 36 / Updated: Joseph DiVerdi 146 May 31 '10 at 06:29

How to extract Bruker fid data - in topspin and xwinnmr - to ascii format?

4 1 24384
answers votes views
Hi and thanks for answering my prev. questions! Decided to ask this one: How can I convert fid data (ser file) to plain...
Posted: Magnethead 42 / Updated: Ulrich Haunz 210 Dec 04 '14 at 04:16

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

4 1 23816
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

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

4 1 16363
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

How does pipe estimates Haight and DHeight?

4 1 4k
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

VnmrJ 2.2D on Ubuntu 10.04

4 3 8k
answers votes views
Dear all, I was wondering whether someone managed to install the VnmrJ software of Varian (2.2 D) on a Ubuntu based sys...
Posted: Tom de Greef 31 / Updated: maxm00d 1 Nov 08 '12 at 05:24

processing varian data in topspin?

4 1 22483
answers votes views
Hi I have recently moved to a lab which has a varian magnet, in the past I have only used brukers. The people here use ...
Posted: Thomas Garner 81 / Updated: surya 11 Feb 28 '11 at 06:28

Area of effect?

4 1 5k
answers votes views
What defines the area of effect of nuclear magnetic resonance? Is it the magnetic field? the frequency? Or just the diam...
Posted: M Kieselbach 11 / Updated: Dmitry Mainichev 31 Mar 22 '11 at 19:00

setting up solid echo on bruker

4 1 11139
answers votes views
Hello, I need to set up aquisition parameters for an echo solid sequence on bruker. In order to analyse deuteraed sample...
Updated: silvernmr 11 Mar 06 '11 at 12:39

two triplets and no quartet?

4 1 7k
answers votes views
Hello all, I have spent approximately 4 hours trying to analyze an H NMR consisting of two doublets of doublets (pe...
Posted: Kelsey O'Dell 11 / Updated: joenmr 1 Feb 18 '15 at 10:44

data processing

4 1 6k
answers votes views
HELLO NMR WIKI ERS Could you please give information about the standred reference values of LINEAR PRIDICTION FORWRAD...
Updated: sri 71 May 24 '11 at 02:45

Downfield carbon paired with a upfield proton

4 1 5k
answers votes views
Dear sirs and madams, I have a natural product whose two carbon resoances are appearing at 46 and 56 ppm but theirs prot...
Posted: Jonnala Kotesh Kumar 11 / Updated: nvgramosa 11 Oct 08 '11 at 09:08

peak missing in nh hsqc protein nmr

4 0 19131
answers votes views
Dear NMR wikiers I am assigning 95 aminoacid residue protein . I can see 76 cross peaks in N H HSQC on 700 vnmr cryob ...
Updated: sri 71 Aug 25 '11 at 00:05

Problem with the gradient shimming

4 0 7k
answers votes views
Dear Friends, I've recently encountered a problem with gradient shimming that has never happened to me before. I can't ...
Posted: dkubicki 11 / Updated: Charlie Fry 91 Nov 16 '12 at 09:02

Simple 1H-NMR Assignment Query

4 1 5k
answers votes views
Hi guys, sorry to be really cheeky and sign up simply to ask for help, but here goes. I've done a simple Grignard addit...
Posted: Brianstorm 11 / Updated: 3nath 11 Oct 26 '11 at 12:53

Spectra from BMRB Chemical shifts

4 0 9k
answers votes views
Is it possible to generate a spectrum from BMRB chemical shifts? I want to generate a spectrum to use as a reference fo...
Posted: Andreas 1 / Updated: delaglio 1361 Dec 11 '11 at 14:15

Difficulties with wobbing.

4 1 5k
answers votes views
Hello, dear NMR-comrades! I work on Bruker AVANCE II 400 MHz NMR-spectrometer and today I had some troubles with wobbi...
Posted: Alexander Abakumov 11 / Updated: Jerry Hirschinger 199 Jul 16 '12 at 07:55

Amplifier problem

4 0 8k
answers votes views
Hi.We have a 500 MHz AVANCE-DRX spectrometer and I have a question about it .How we can understand that the amplifier ha...
Posted: shokoufeh karimnia 1 / Updated: Nonai 1 May 22 '14 at 00:45

lose the lock

4 0 7k
answers votes views
Recently the TOPSPIN always popup a windows "L-TRX board overtemperature error occurs" Then the lock is lost, and the lo...
Updated: Roja 26 Jan 07 '13 at 15:58

Which minimum distance between two magnets?

4 0 8k
answers votes views
Dear all, how do you determine the minimum distance between two high-field magnets? Is it that their 5-gauss lines mus...
Posted: oxy 31 / Updated: John Hollerton 96 Apr 22 '13 at 05:56

Bruker & Varian phase correction parameters

4 0 6k
answers votes views
Hi, I am an undergraduate student who is doing a chemistry/computing project. I have chosen to write a simple C program...
Updated: Jean Davidson 1 Mar 30 '13 at 12:23

question about NQR

4 0 5k
answers votes views
Hi.We have a 500MHz BRUKER AVANCE spectrometer.unfortunately its has been quenched.we have 3 probes:5mmQNP , 5mmBBI and ...
Posted: shokoufeh karimnia 1 / Updated: SankarampadiAravamudhan 91 Jun 04 '13 at 04:44

How to recover from quenched or dried magnet?

4 0 21765
answers votes views
We have got a donated AQR/p with Spectrospin 300 magnet and there is no helium inside. It was sitting in the warehouse f...
Posted: agoo 1 / Updated: Jerry Hirschinger 199 Oct 04 '13 at 09:58

how to get a 1H-15N HMBC spectroscopy

4 0 8k
answers votes views
hi All, I run a 1H-15N HMBC experiment on a Bruker AVANCE III 600 MHz spectrometer. But I fail to get the long- range ...
Posted: nmrqibebt 1 / Updated: Kirk Marat 711 Dec 09 '13 at 07:48

Diagnosing 1D selective NOE issues

4 0 8k
answers votes views
I'm trying to diagnose a possible issue performing a selective 1D NOE (selnogp) on a Bruker Avance II 500Mhz with TopSpi...
Updated: kyleabeauchamp 1 Mar 22 '14 at 09:48

195Pt experiment setup help needed

4 0 7k
answers votes views
We just bought a new console (with Topspin 3.2)for our Bruker 400 and noticed that not all experiments that we previousl...
Posted: IA 1 / Updated: Kirk Marat 711 Apr 04 '14 at 13:48

Topspin 3.2.1 - 1D TOCSY in with differing mixing times

4 1 8k
answers votes views
Hello, I work a lot with compounds containing numerous carbohydrate groups. Therefore I use frequently 1D-TOCSY experim...
Posted: zablociak 21 / Updated: Alain Pagelot 1 Jun 10 '14 at 02:38
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