Data Set Title: "Reference data for isolated 2'-hydroxyacetophenone - Part 2"

Data Set Authors: Maris, Assimo   University of Bologna   ORCID 0000-0003-2644-0023

Contact Person:   Maris, Assimo   University of Bologna   ORCID 0000-0003-2644-0023   assimo.maris@unibo.it

Data Set License: This data set is distributed under Creative Commons Attribution 4.0 International.
To view a copy of this license, visit https://creativecommons.org/licenses/by/4.0/

Publication Year: 2026


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Abstract

This dataset contains the experimentally observed rotational transition frequencies of isolated 2'-hydroxyacetophenone (2HA), recorded in two spectral regions: (i) 2-8 GHz using chirped-pulse Fourier-transform microwave (CP-FTMW) spectroscopy in a pulsed supersonic jet and (ii) 59.6-74.4 GHz using free-jet absorption Stark-modulated millimeter-wave spectroscopy.
The spectroscopic analyses were performed with both the CALPGM suite and the XIAM program using Hamiltonians based on the semirigid rotor formalism (Watson's S-reduction in the I-r representation) supplemented with terms accounting for methyl-group internal rotation. 


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Data Set Contents

The dataset is distributed as the compressed archive DATA_FIT_2HA.zip with the following structure:

DATA_FIT_2HA.zip
|   DATA_FIT_2HA_README.txt
+---CALPGM
|   2ha.cat
|   2ha.egy
|   2ha.fit
|   2ha.int
|   2ha.lin
|   2ha.out
|   2ha.par
|   2ha.var
+---XIAM
|   2ha_fit.xi
|   2ha_fit.xo
|   2ha_pred.xi
|   2ha_pred.xo
    

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Dataset Documentation

The CALPGM directory contains files used for fitting and prediction with the SPFIT/SPCAT suite.
Fitting Input Files for SPFIT
2ha.par: trial spectroscopic parameters.
2ha.lin: assigned experimental transition lines.
Fitting Output Files of SPFIT
2ha.fit: fit results and statistical information.
Prediction Input Files for SPCAT
2ha.var: spectroscopic parameters.
2ha.int: intensity calculation parameters.
Prediction Output Files for SPCAT
2ha.cat: predicted spectral catalog.
2ha.egy: calculated energy levels.
2ha.out: detailed output.

The XIAM directory contains files used for fitting and prediction with the XIAM program.
Fitting Input File for XIAM
2ha_fit.xi: trial spectroscopic parameters and assigned experimental transition lines.
Fitting Output File of XIAM
2ha_fit.xo: fit results and statistical information.
Prediction Input File for XIAM
2ha_pred.xi: spectroscopic and intensity calculation parameters.
Prediction Output File of XIAM
2ha_pred.xo: predicted spectral catalog.

Methodology
The rotational spectra were assigned and analyzed using two independent approaches.
The CALPGM program suite (SPFIT/SPCAT) is available at https://spec.jpl.nasa.gov/ and the format of the files is described here: https://spec.jpl.nasa.gov/ftp/pub/calpgm/spinv.pdf
The XIAM program and the description of the format of the files are available at http://info.ifpan.edu.pl/~kisiel/introt/introt.htm#xiam

File Specifics
All files are plain-text ASCII files and can be opened and inspected with any standard text editor.

Notes
The data provided in this repository were generated to support and reproduce the results reported in the following publication:
Baroncelli, F.; Stanganini, R.; Blanco, S.; Maris, A.
Broadband Microwave Spectroscopy of 2'-Hydroxyacetophenone: A Complex Oxygenated Ring for Interstellar Searches.
Physchem
