spectrum
********
Convolutes singlet spectrum with gaussian or lorentzian function
The following table contains the defaults input options for the calculator, The default `OPTIONAL` means this option is switched off, if no input is given. 
`REQUIRED` arguments have to be specified, otherwise an error is thrown.

.. list-table::
   :header-rows: 1
   :widths: 30 20 15 15
   :align: center

   * - Property Name
     - Default Value
     - Description
     - Valid Input
   * - input
     - OPTIONAL
     - orbfile to read from, otherwise use job_name
     - 
   * - output
     - OPTIONAL
     - ASCII output filename, if not given use job_name
     - 
   * - job_name
     - system
     - | Input file name without extension, also used for intermediate
       | files
     - 
   * - fwhm
     - 0.2
     - peak width in eV
     - float+
   * - lower
     - 0.0
     - lower bound of spectrum in eV
     - float+
   * - upper
     - 3.5
     - upper bound of spectrum in eV
     - float+
   * - points
     - 100
     - datapoints between upper and lower to calculate
     - int+
   * - type
     - energy
     - print put energy/wavelength (eV/nm)
     - | energy
       | wavelength
   * - minexc
     - 0
     - lowest exciton to include in spectrum
     - int+
   * - maxexc
     - 10000
     - highest exciton to include in spectrum
     - int+
   * - shift
     - 0.0
     - shift spectrum by amount of eV
     - float+
.. note::
   An *xml* file containing the defaults for the `spectrum` calculator can be created via `-p spectrum -o FILENAME` command line options `