NMR Sim
Last Change : Mon Nov 14 10:00:34 MEZ 1994
NMR Sim is a program for the simulation of a wide range of NMR pulse
experiments. The output of the simulation is a FID or SER file in
the format used on Bruker spectrometers. NMR Sim uses as input the standard
Bruker pulse sequences and experiment definition parameters.
The program is designed to simulate the behaviour of general
homo and heteronuclear spin systems.
The simulation is based on the solution of the quantum mechanical Liouville
equation. The spin system evolution during the radio frquency pulse is taken
into account, therefore you may simulate rotating frame magnetisation
experiments (TOCSY, HOHAHA ). The Bloch module allows to visualise the time
developement of the nuclear magnetisation vector during various experiments.
News in 940131 release
- NMR Sim is now available on following platforms:
- MS Windows
- MS Windows - NT
- Aspect Station 1
- SGI Workstations with IRIX 4.- or 5.-
- Bloch Simulator
- Simulation of mixtures allows realistic simulation of isotopes with
natural abundance less than 100 %.
- Pulse program display in graphical form.
The Bruker pulse programs are shown in a simple graphical form.
- Third rf channel implemented - this allows the simulation of
heteronuclear 3D experiments.
- Complicated pulse programs are automatically compiled - the
manual compilation procedure is further not necessary.
New version 940901
The version 940901 is avaliable for Unix platforms only.
It contains following new feaatures:
- Support of pulse program languague for AMX/ARX/DMX Bruker
spectrometers. ( 940131 supported AMX only )
- Further devellopement of pulse program display - zoom for
complicated sequences.
- All user data ( spin system descriptions, lists ....)
are now in user private directory: "home"/NMRSIM_SESSION.
- All known bugs in 940131 fixed.
Examples
NMR Sim comes with several predefined
example experiments . Every example contains all the setting of
all necessary parameters, the results are printed in manual.
Spin system definition
The role of the sample on the real spectrometer plays for the simulation
the spin system definition.
The spin system is in NMR Sim defined using simple languague, you need
the chemical shifts and J-couplings for all nuclei.
- This is a definition of example spin system with spin equivalency
; 3 equivalent spin - 1/2 nuclei labelled a with
; a chem. shift of 3.6 ppm
proton 3*a 3.6
; nucleus b has spin 3/2, shift 8.3 ppm and t1 = t2 = 0.32 s
nucleus b j3/2 8.3 t= 0.32
; nucleus c is C13
carbon c13 83 t= 0.32
; CH coupling
weak a b 103
- This is the definition of a mixture of two CH3-H molecules,
one with C13, 2nd wit C12. The weights are identical with the natural
abundance of C13 isotope !
molecule alpha 1.108
proton 3*a 10
proton b 11
carbon x 130
couple a b 11
couple a x 80
endmol
molecule beta 98.882
proton 3*a 10
protom b 11
couple a b 11
endmol
Performance
Following table shows the program performance. All times are in seconds.
The values for MS Windows 3.1 are valid for "low end" 33 MHz 80386
Compaq DeskPro computer with 4MB memory and 80387 coprocessor.
Experiment Spin system Dimension MS-Windows SGI Indy Indy/4600
------------------------------------------------------------------------------------
Selective Cosy ABC TD=4k 8 0.6 0.5
------------------------------------------------------------------------------------
Jres ABC 1024x256 135 4 2.7
------------------------------------------------------------------------------------
Cosy ABC 1024x256 160 8
------------------------------------------------------------------------------------
DQ Cosy ABC 1024x256 180 14
------------------------------------------------------------------------------------
Dr. Pavel Kessler, Email: pavel@bruker.de
Bruker Analytische Messtechnik GmbH, D-76287 Rheinstetten