1、Designation:E291113Standard Guide forRelative Intensity Correction of Raman Spectrometers1This standard is issued under the fixed designation E2911;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in
2、 parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This guide is designed to enable the user to correct aRaman spectrometer for its relative spectral-intensity responsefunction using NIST Standard Re
3、ference Materials2in the224X series(currently SRMs 2241,2242,2243,2244,2245,2246),or a calibrated irradiance source.This relative intensitycorrection procedure will enable the intercomparison of Ramanspectra acquired from differing instruments,excitationwavelengths,and laboratories.1.2 The values st
4、ated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 Because of the significant dangers associated with theuse of lasers,ANSI Z136.1 or suitable regional standardsshould be followed in conjunction with this practice.1.4 This standard does not
5、purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:3E13
6、1 Terminology Relating to Molecular SpectroscopyE1840 Guide for Raman Shift Standards for SpectrometerCalibrationE2529 Guide for Testing the Resolution of a Raman Spec-trometer2.2 ANSI Standard:4Z136.1 Safe Use of Lasers3.Terminology3.1 DefinitionsTerminology used in this practice con-forms to the d
7、efinitions in Terminology E131.4.Significance and Use4.1 Generally,Raman spectra measured using grating-baseddispersive or Fourier transform Raman spectrometers have notbeen corrected for the instrumental response(spectral respon-sivity of the detection system).Raman spectra obtained withdifferent i
8、nstruments may show significant variations in themeasured relative peak intensities of a sample compound.Thisis mainly as a result of differences in their wavelength-dependent optical transmission and detector efficiencies.Thesevariations can be particularly large when widely different laserexcitati
9、on wavelengths are used,but can occur when the samelaser excitation is used and spectra of the same compound arecompared between instruments.This is illustrated in Fig.1,which shows the uncorrected luminescence spectrum of SRM2241,acquired upon four different commercially availableRaman spectrometer
10、s operating with 785 nm laser excitation.Instrumental response variations can also occur on the sameinstrument after a component change or service work has beenperformed.Each spectrometer,due to its unique combinationof filters,grating,collection optics and detector response,has avery unique spectra
11、l response.The spectrometer dependentspectral response will of course also affect the shape of Ramanspectra acquired upon these systems.The shape of this re-sponse is not to be construed as either“good or bad”but is theresult of design considerations by the spectrometer manufac-turer.For instance,as
12、 shown in Fig.1,spectral coverage canvary considerably between spectrometer systems.This istypically a deliberate tradeoff in spectrometer design,wherespectral coverage is sacrificed for enhanced spectral resolution.4.2 Variations in spectral peak intensities can be mostlycorrected through calibrati
13、on of the Raman intensity(y)axis.1This guide is under the jurisdiction of ASTM Committee E13 on MolecularSpectroscopy and Separation Science and is the direct responsibility of Subcom-mittee E13.08 on Raman Spectroscopy.Current edition approved July 1,2013.Published July 2013.DOI:10.1520/E2911132Tra
14、demark of and available from NIST Office of Reference Materials,100Bureau Drive,Stop 2300,Gaithersburg,MD 20899-2300.http:/www.nist.gov/srm.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume in
15、formation,refer to the standards Document Summary page onthe ASTM website.4Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United Sta
16、tes1 The conventional method of calibration of the spectral re-sponse of a Raman spectrometer is through the use of aNational Metrology Institute(NMI),for example,NIST,trace-able calibrated irradiance source.Such lamps have a definedspectral output of intensity versus wavelength and proceduresfor their use have been published(1)5.However,intensitycalibration using a white-light source can present experimentaldifficulties,especially for routine analytical work.Calibratedtungsten halogen lamps hav
