trickl_1989
===========

T\. Trickl, E\. F\. Cromwell, Y\. T\. Lee and A\. H\. Kung, "State\-selective ionization of nitrogen in the X 2Sigma\_g\+ v\+ = 0 and v\+ = 1 states by two\-color \(1\+1\) photon excitation near threshold", J\. Chem\. Phys\. 91, 6006 \(1989\)

`Source record <https://github.com/LupoLab/optmat/blob/main/src/optmat/data/sources/trickl_1989.toml>`__ · :doc:`Catalogue </the-data/sources>` · :doc:`Review register </register>`

DOI: `10\.1063/1\.457417 <https://doi.org/10.1063/1.457417>`__

**Source kind:** measurement

**Recorded technique:** Two\-colour \(1\+1\) resonance\-enhanced photoionisation of N2 in a pulsed, collimated jet \(estimated density 1e13 cm^\-3\)\: XUV light \(frequency\-tripled, pulse\-amplified cw ring dye laser, bandwidth slightly above 210 MHz\) excites the c4' 1Sigma\_u\+ \(v' = 0, 1\) Rydberg states from X 1Sigma\_g\+ \(v'' = 0\), and a second pulsed dye laser \(Coumarin 460, bandwidth 0\.5 cm^\-1, \<= 1 mJ\) is scanned across the N2\+ X 2Sigma\_g\+ v\+ = 0 and v\+ = 1 thresholds; ions extracted by a delayed 23\.6 V/cm pulse \(field\-free ionisation\), mass\-selected by time of flight\. Laser 1 calibrated with the Autoscan wavemeter against I2 lines; laser 2 against a neon reference spectrum \(pp\. 6006\-6007, 6009\)\.

**Materials in structured entries:** N2

**Dataset quantities:** ionization\_energy

**Contents:** 3 datasets; 0 formulas.

Curation notes
--------------

PDF pages 2\-8 = journal pages 6006\-6012 \(PDF page 1 is the publisher's cover sheet\)\. Identity checked on the first page\. Nitrogen only\.

THE IONISATION ENERGY \(p\. 6010, and the abstract, p\. 6006\)\: 'The resulting ionization energy of N2 is 125 666\.959\(67\) cm^\-1\.' It is the sum of the c4' \<\- X \(0,0\) R0 line of Table I \(104 326\.451\(25\) cm^\-1, from X \(v'' = 0, J'' = 0\) to c4' \(v' = 0, J' = 1\)\) and the limit of the nd delta\_g 1Delta\_g Rydberg series excited from c4' \(0, J' = 1\), nu\_inf = 21 378\.952\(22\) cm^\-1 \('\+\-0\.060 cm^\-1, if one includes the calibration error'; Eq\. \(2\), 50 \<= n \<= 74, Table II\), less the rotational energy of the N\+ = 4 level to which the series converges \(the N\+ = 4 threshold computed from the literature, Refs\. 30 and 31, and Table I, is 21 378\.793 cm^\-1\)\. It is therefore the energy from the neutral's rotationless level X 1Sigma\_g\+ \(v = 0, J = 0\) to the ion's rotationless level X 2Sigma\_g\+ \(v\+ = 0, N\+ = 0\); the ion's spin\-doublet splitting 'is very small and cannot be resolved in our experiment' \(p\. 6009\)\. Check \(not printed\)\: 104 326\.451 \+ 21 378\.952 = 125 705\.403 cm^\-1, and 125 705\.403 \- 125 666\.959 = 38\.444 cm^\-1 is the N\+ = 4 rotational energy the paper subtracted \(N\(N\+1\) B\+ = 20 B\+ with B\+ = 1\.922 cm^\-1\)\. The uncertainty \(67\) is stated without a confidence level; it is close to the series limit's 0\.060 cm^\-1 with the calibration error, combined with the R0 line's 0\.025 cm^\-1\.

A SECOND DETERMINATION \(p\. 6008\)\: the field\-dependent threshold of the ion signal from c4' \(0, J' = 1\), fitted by nu\_thr\(E\) = 21 340\.54\(56\) cm^\-1 \- 5\.55 sqrt\(E \[V/cm\]\) \(Eq\. \(1\), E \<= 100 V/cm, thresholds at half\-rise\), plus the R0 line\: 'an ionization energy for N2 of 125 666\.99\(56\) cm^\-1 which is close to the value given by Ogawa and Tanaka of 125 666\.8 cm^\-1', taken to correspond to ions in N\+ = 0 \(the N\+ = 1 and 2 levels are 3\.84 and 11\.53 cm^\-1 higher\)\. Recorded as a check value, superseded within the paper by the series limit\.

v\+ = 1\: the paper gives no ionisation energy to X 2Sigma\_g\+ v\+ = 1\. The spectrum of Fig\. 2\(d\) \(from c4' \(v' = 1, J' = 1\), laser 2 near 465\.7 nm\) 'could not be analyzed because of the lower resolution chosen for this scan' \(p\. 6011\)\.

In eV \(not printed; hc = 1\.239841984e\-4 eV cm\)\: 125 666\.959 cm^\-1 = 15\.580717 eV \(\+\-8\.3e\-6 eV\); 125 666\.99 cm^\-1 = 15\.58072 eV\.

NOT EXTRACTED \(notes only\)\: \- Table I \(p\. 6007\)\: N2 transition frequencies \(cm^\-1\) measured in single\-laser \(1\+1\) ionisation\: c4' \<\- X \(0,0\) R0\-R2 104 326\.451\(25\), 104 330\.190\(25\), 104 333\.802\(25\); c4' \<\- X \(1,0\) R0, R1 106 372\.005\(35\), 106 374\.849\(35\); c3 \<\- X \(0,0\) R0\-R2, Q1, Q2; b' \<\- X \(2,0\) R0\-R2; with the lines computed from the literature \(Carroll et al\., Lofthus, Proch & Trickl, Bendtsen, Vanderslice et al\.\)\. XUV transition frequencies, not ionisation data\. \- Table II \(p\. 6011\)\: 25 measured nd delta\_g Rydberg lines \(n = 50\-74, 21 335\.260 to 21 358\.923 cm^\-1\) from c4' \(0\) J' = 1, with Eq\. \(2\)'s values \(R = 109 735\.17 cm^\-1, mass\-corrected\) and the differences \(within \+\-0\.11 cm^\-1\); fitted delta = \-0\.088\(22\)\. \- The J' = 2 and 3 series \(Figs\. 2\(b\), 2\(c\)\) converge to N\+ = 5 and 6 after a 0\.73 cm^\-1 correction attributed to a calibration change of laser 2 or a Stark shift \(p\. 6011\); quantum defects \-0\.18\. \- Other energies quoted\: the N2\+ A 2Pi\_u threshold 9016\.021\(8\) cm^\-1 above the X threshold \(Benesch et al\., p\. 6007\); omega\_e of N2\+ X 2207\.0366 \+\- 0\.05 cm^\-1 \(Gottscho et al\., p\. 6010\)\.

**Recorded bibliographic identity status:** VALIDATED\_WITH\_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.

Datasets
--------

trickl\_1989/ie\_N2
~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "ie_N2",
     "material": "N2",
     "table": "text",
     "quantity": "ionization_energy",
     "unit": "cm-1",
     "abscissa": "label",
     "use": "primary",
     "parameters": {
       "kind": "adiabatic",
       "final_state": "X 2Sigma_g+ (v+ = 0, N+ = 0)",
       "initial_state": "X 1Sigma_g+ (v = 0, J = 0)"
     },
     "uncertainty": {
       "column": true,
       "level": "not stated"
     }
   }

1 inline points in the source record.

p\. 6010 \(and abstract, p\. 6006\)\: 'The resulting ionization energy of N2 is 125 666\.959\(67\) cm^\-1', from the Rydberg series limit converging to N\+ = 4, reduced to N\+ = 0 with the literature rotational energy \(record notes\)\. = 15\.580717 eV\. The confidence level of \(67\) is not stated\.

trickl\_1989/threshold\_N2
~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "threshold_N2",
     "material": "N2",
     "table": "text",
     "quantity": "ionization_energy",
     "unit": "cm-1",
     "abscissa": "label",
     "use": "check",
     "parameters": {
       "kind": "adiabatic",
       "final_state": "X 2Sigma_g+ (v+ = 0, N+ = 0)",
       "initial_state": "X 1Sigma_g+ (v = 0, J = 0)"
     },
     "uncertainty": {
       "column": true,
       "level": "not stated"
     }
   }

1 inline points in the source record.

p\. 6008\: the zero\-field extrapolation of the ion\-signal threshold \(Eq\. \(1\), half\-rise, E \<= 100 V/cm\) plus the c4' \<\- X \(0,0\) R0 line, 'an ionization energy for N2 of 125 666\.99\(56\) cm^\-1', which 'corresponds to ions in the N\+ = 0 rotational level'\. The paper's less precise determination, superseded by ie\_N2\: a check\.

trickl\_1989/ogawa\_1962\_N2
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "ogawa_1962_N2",
     "material": "N2",
     "table": "text",
     "quantity": "ionization_energy",
     "unit": "cm-1",
     "abscissa": "label",
     "use": "reproduced",
     "reproduced_from": [
       "M. Ogawa and Y. Tanaka, Can. J. Phys. 40, 1593 (1962)"
     ],
     "parameters": {
       "kind": "adiabatic",
       "final_state": "X 2Sigma_g+ (v+ = 0)"
     }
   }

1 inline points in the source record.

p\. 6008\: 'the value given by Ogawa and Tanaka of 125 666\.8 cm^\-1' \(Ref\. 30\(a\)\); Ref\. 30\(b\)\: 'Ogawa and Tanaka do not give an error limit for their measurements\. The measured and calculated numbers in Table 1 of Ref\. 30\(a\) differ typically by less than 0\.5 cm^\-1\.' Rydberg\-series limit from absorption; the levels are not stated here\.

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 </register>` for the checks and decisions.