pengqian_1997 ============= Wang Peng\-qian, Xie Xiao\-bo and Sun Tao\-heng, Chin\. Phys\. Lett\. 14, 740 \(1997\) `Source record `__ · :doc:`Catalogue ` · :doc:`Review register ` DOI: `10\.1088/0256\-307x/14/10/006 `__ **Source kind:** measurement **Recorded technique:** Resonance\-enhanced third\-harmonic generation in a pulsed methane jet \(850 Torr backing, about 5 % of it assumed at the focus\) of a frequency\-doubled, tunable dye laser \(1\-3 mJ, 10 ns, 0\.5 cm^\-1\)\: third\-harmonic spectra from 105\.3 to beyond 111\.3 nm \(VUV\) and 92\.75 to 96\.67 nm \(XUV\), normalized to the cube of the input energy\. **Materials in structured entries:** None recorded. **Dataset quantities:** None recorded. **Contents:** 0 datasets; 0 formulas. Curation notes -------------- No third\-order value is extracted\: the paper prints no susceptibility or hyperpolarizability, only relative third\-harmonic spectra \(Figs\. 1, 2\) and the cubic power dependence \(Fig\. 3\)\. Eq\. \(1\), p\. 740\: I\(3w\) proportional to N^2 \|chi\(3\)\(3w\)\|^2 I\(w\)^3 F\(b Delta k\) \(after Lago, Hilber and Wallenstein 1987\), with no absolute calibration\. The spectra show a vibrational progression of methane's excited states near 89900\-95000 cm^\-1 \(spacing 820 \+\- 20 cm^\-1, p\. 742\), i\.e\. resonantly enhanced chi\(3\) at three\-photon resonances in the VUV\: not relevant to the nonresonant Kerr and THG coefficients\. The conversion efficiency of methane is 'at least one order less than that in CO' in the same regions \(p\. 743\), a qualitative statement only\. The library's author names are inverted \(the paper prints WANG Peng\-qian, XIE Xiao\-bo, SUN Tao\-heng\: family names Wang, Xie, Sun\); the source id keeps the library's order\. **Recorded bibliographic identity status:** VALIDATED\_WITH\_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents. Datasets -------- No datasets are recorded. Formulas -------- No formulas are recorded. Corrections ----------- No dataset errata are recorded in this source record. Formula corrections, where recorded, appear with their formulas above. Curation notes may also discuss corrections or unresolved interpretation. Consult the :doc:`review register ` for the checks and decisions.