The Spectra Formats

As stated on the opening page of this website, the spectra are available in three formats:
GIF: suitable for most graphics programs and web browsers
DAT: ASCII suitable for Excel (and other spreadsheets) and CLIMAX
JCAMP-DX: the standard ASCII format for infrared and Raman spectroscopy

DAT

This type of file can be imported directly into a spreadsheet or other graphical display package. It is a simple (x,y,e) ASCII format with a file header:
ACETONITRILE Ref: J.CS. Farad.Trans. 87 (1991) 539. J.W.White, ANU, Canberra, Australia
C (CM-1) COUNTS ERROR
1.613200E+01 4.913682E-10 7.514824E-11
1.621266E+01 6.585508E-10 8.950449E-11
1.629372E+01 6.133741E-10 8.619769E-11
1.670516E+01 5.965735E-10 8.303958E-11
.
.
3.972105E+03 3.953404E-10 2.531102E-11
3.991966E+03 3.758412E-10 2.471038E-11
The first line is the name of the compound, its principal investigator (this is not necessarily the person who actually measured the spectrum), their affiliation and the literature reference (if known). The second line defines the units, for the energy transfer (i.e. x) axis all the spectra are given in units of wavenumbers, cm-1, (1 meV=8.067 cm-1). The counts (i.e. y) column is the scattered intensity and is directly proportional to the scattering function S(Q,w. The error column (i.e. z) is given by the square root of the number of counts, since Poisson statistics apply to the measurement process.
It is also suitable for use with the INS spectra analysis program ACLIMAX..

JCAMP-DX

This is the IUPAC standard format for the interchange of vibrational spectra. This format allows INS spectra to be loaded into an infrared or Raman spectrometer for direct comparison with optical data. The format is very flexible and is described in detail in
R. S. McDonald and P. R. Wilks Jr., "JCAMP-DX: A Standard Format for Exchange of Infrared Spectra in Computer Readable Form", Applied Spectroscopy 42 (1988) 151-162
See http://www.isas-dortmund.de/projects/jcamp/protocol.html for an online version of this paper.
and
J. G. Grasselli, "JCAMP-DX: A Standard Format for Exchange of Infrared Spectra in Computer Readable Form", Pure and Applied Chemistry 63 (1991) 1781-1792.
An example is shown below. Lines beginning with ## are comment lines. The first five lines define the origin of the spectrum, the next 12 give information as to how the data is organised, the data then follows and is terminated by ##END=
##TITLE= Copper formate ref:J.Chem.Soc.Faraday.Trans 93 (1997) 2569-2577 P.C.H.Mitchell, University of Reading
##JCAMP-DX= 4.24
##DATA TYPE= INELASTIC NEUTRON SCATTERING
##ORIGIN= TFXA, ISIS
##OWNER=
##NPOINTS= 996
##XUNITS= 1/CM
##YUNITS= S(Q,w)
##RESOLUTION=
##FIRSTX= 1.600000E+01
##LASTX= 3.996000E+03
##XFACTOR= 1.0
##YFACTOR= 2.027835E+06
##FIRSTY= 6.883899E-01
##MAXY= 5.185178E+00
##MINY= 4.931368E-01
##XYDATA= (X++(Y..Y))
16.000 001395941 001055813 001000000 001110662 001281299 001535087
40.000 001912739 002303294 002639247 003124483 003366158 003506463
64.000 003527803 003330772 003643439 003699664 003751660 003409445
88.000 004229072 004171009 003863634 003682591 003906787 003691139


3952.000 002525898 002524602 002524602 002524602 002524602 002388336
3976.000 002384646 002384646 002384646 002385318 002463903 002463903
##END=
The file format has been tested on a number of machines and is usually importable without difficulty. In some cases, the program will reject the data if it is not an infrared spectrum. In this case on line 3 (## DATA TYPE) "Inelastic Neutron Scattering" should be changed to "Infrared Spectrum" and on line 8 (##YUNITS) "S(Q,w)" should be changed to "Absorbance".

GIF

This is the standard Internet graphics file. It can be viewed by nearly all web browsers and by most graphics software. It can be placed into any Office document and scaled accordingly. The title contains the chemical name or formula, the name and affiliation of the principle investigator and a reference if it has been published.