# Processing and plotting for rovibrational line lists (DAT2GR)

The DAT2GR program is used to process and to generate plots from rovibrational infrared and Raman line lists generated by the RCI and RVCI programs that are part of the VSCF and VCI progam.

DAT2GR,options

The DAT2GR program allows for the processing of rovibrational line lists (IR and Raman) to modify data, apply line-broadening and temperature effects or generate plots. The file containing the line list must be generated before by the RCI or RVCI methods which are part of the VSCF or VCI programs. DAT2GR does not require any XSURF or VSCF calculations prior to its call, but requests at least a Hartree-Fock calculation, which is always needed in Molpro.
The following options are available:

• EXTERN=filename This keyword is mandatory and requests the filename of the file containing the input file (rovibrational line list) as generated from the VSCF or VCI programs.
• DUMP=filename This key defines the output file to be generated.
• TYPE=string (=’IR’ Default) This option controls the type of line list to be handled, but it will be set according to the input line list type anyway. Options are ’IR’ or ’Raman’.
• METHOD=string (=’INT’ Default) This option controls the method of data handling, e.g. whether the data should be modified/filtered or (re-)calculated. Options are ’MOD’ (modify/filter exisiting line list), ’INT’ (calculate T-dependent intensities from exisiting intensities at $T=0$ K), ’INT_TM’ (calculate Raman intensities from transition moments $R_0$ and $R_2$ in the input line list).
• PROFILE=string (=’GAUSSIAN’ Default) This option controls the line shape to be used for accounting of line-broadening or in the case of data modification/filtering (METHOD=’MOD’) what's to be done. PROFILE=’Lines’ will return a line list again without any broadening. PROFILE=’Lorentz’ sets the line shape to be Lorentzians, PROFILE=’Gauss’ will use Gaussians. PROFILE=’Voigt’ specifies a line shape from numerical convolution of Gaussians and Lorentzians, which is numerically expensive. The combined half-widths $\sigma$ for the Gaussian and $\gamma$ for the Lorentzian line shape are calculated from the temperature and pressure using a physical description. PROFILE=’Gaussian’ specifies a simple Gaussian line shape with half-width SIGMA. For METHOD=’MOD’ the options are PROFILE=’SORT’ to sort the data by the column specified with the keyword SORT or PROFILE=’SYMSEL’ to apply symmetry selection rules.
• SORT=n (=12 (frequencies) Default) PRINT=2 enables additional printout.
• EINC=value (= 0.1 Default, in cm$^{-1}$) Incremental energy (resolution) to be considered.
• EMAX=value (= 5000 Default, in cm$^{-1}$) This option specifies the maximum energy of the spectral range to be considered.
• EMIN=value (= 0 Default, in cm$^{-1}$) This option specifies the minimum energy of the spectral range to be considered.
• TINC=value (= 100 Default, in K) Temperature increment to be considered.
• TMAX=value (=0 (off) Default, in K) Maximum temperature to be considered. Setting only TMIN will set TMAX to the same value.
• TMIN=value (=0 (off) Default, in K) Minimum temperature to be considered. Setting only TMAX will set TMIN to the same value.
• TLIST=string (off Default, in K) List of temperatures to be considered, e.g. ’200,250,300’. Combinable with other temperature-keywords. to be considered.
• FWHM=value Full width at half maximum (FWHM) to be used for line-broadening (Gaussian, Lorentzian).
• FWHM_LIST=string (off Default) Define a list of values for the FWHM to be used with Gaussian or Lorentzian line-broadening.
• GAMMA=value Half width (HWHM) to be used for Lorentzians.
• GAMMA_LIST=string (off Default) Define a list of scaling parametes GAMMA_SCALE for the half-width (HWHM) for Lorentzians used in Voigt profile, e.g. ’1.0,3.0,10.0’.
• GAMMA_SCALE=value (=1.0 (off) Default) Scale the half-width (HWHM) for Lorentzians used in Voigt profile as $\gamma$/GAMMA_SCALE.
• SIGMA=value (= 1.0 Default, in cm$^{-1}$) Half width to be used for Gaussians if PROFILE=’GAUSSIAN’.
• SIGMA_LIST=string (off Default) Define a list of scaling parametes SIGMA_SCALE for the half-width for Gaussians used in Voigt profile, e.g. ’1.0,3.0,10.0’.
• SIGMA_SCALE=value (=1.0 (off) Default) Scale the half-width for Gaussians used in Voigt profile as $\sigma$/SIGMA_SCALE.
• PUNIT=string (=’atm’ Default) Pressure unit.
• PINC=value (= 0.1 atm Default, in PUNIT) Pressure increment to be considered.
• PMAX=value (= 1.0 atm Default, in PUNIT) Maximum pressure to be considered.
• PMIN=value (= 1.0 atm Default, in PUNIT) Minimum pressure to be considered.
• PLIST=string (off Default) List of pressures to be considered, e.g. ’1.0,1.1,1.2’. Combinable with other pressure-keywords.
• PRINT=n (=0 (off) Default) PRINT=2 enables additional printout.
• RAMAN_POLANG=value (=90 Default) Raman polarisation angle defining the prefactors mixing the isotropic and anisotropic Raman transition moments for the calculation of Raman intensities.
• RAMAN_FAC(n)=value Set the prefactors for the isotropic and anisotropic Raman transition moments for the calculation of Raman intensities manually. $n=0$ will set the value for $R_0$, $n=2$ the one for $R_2$.
• RAMAN_LFREQ=value (=680 Default, in nm) Raman exciting radiation (laser) frequency.

The following example generates a rovibrational IR spectrum for the spectral range between 900 and 1100 cm$^{-1}$ for the given temperature of 300 K from the line list provided in the file H2CS_IR_VCI_J3.dat and dumps the output to H2CS_IR_VCI_J3_graph.dat.

memory,50,m
logfile,scratch
mass,iso

geometry={
S
C,S,rcs
H1,C,rch,S,ahcs
H2,C,rch,S,ahcs,H1,180
}

rcs = 1.2 ang
rch = 1.0 ang
ahcs = 120 degree

basis=vdz
hf
dat2gr, extern='H2CS_IR_VCI_J3.dat', Emin=900, Emax=1100, Einc=1d-1
dat2gr, type='IR', profile='Voigt', dump='H2CS_IR_VCI_J3_graph.dat', TList='300', print=2

This example generates a Gauss-broadened rovibrational Raman spectrum from 0 to 200 cm$^{-1}$ for a set of FWHM of $\{0.5,1.0,2.0\}$ cm$^{-1}$ and temperatures of $\{5,50,150,295\}$ K from the line list provided in the file H2CS_Raman_RVCI_J3.dat and dumps the output to H2CS_Raman_RVCI_J3_Gauss.dat by re-calculating intensities from the transition moments $R_0$ and $R_2$ and uses a polarization angle of $90^\circ$ and a laser frequency of $514$ nm.

memory,50,m
logfile,scratch
mass,iso

geometry={
S
C,S,rcs
H1,C,rch,S,ahcs
H2,C,rch,S,ahcs,H1,180
}

rcs = 1.2 ang
rch = 1.0 ang
ahcs = 120 degree

basis=vdz
hf
DAT2GR,extern='H2CS_Raman_RVCI_J3.dat',dump='H2CS_Raman_RVCI_J3_Gauss.dat',TLIST='5,50,150,295',METHOD='INT_TM',PROFILE='GAUSS',EMIN=0,EMAX=200,EINC=1d-2,FWHM_LIST='0.5,1.0,2.0',RAMAN_POLANG=90,RAMAN_LFREQ=514