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Analysis of the 1– v’’ Progression of the 3A Band System (c3Pi - a3Pi) in the 13C16O Molecule Spectrum
(2000 Academic Press (Journal of Molecular Spectroscopy), 2000-09-06) Hakalla, Rafał
The 1-0, 1-1, and 1-2 bands of the 3A system of 13CO (c3Π-a3Π) have been recorded for the first time, in the form of discharge emission spectra photographed at high resolution. Preliminary rotational analysis suggests that the v = 1 level of the c3Π state is perturbed in a fashion similar to the v = 0 level, previously observed by Dabrowski et al. (1987. I. Dabrowski, M. Vervolet, and D. C. Wang, Can. J. Phys. 65, 1171-1177). Rotational combination differences from the 1720 measured lines have been used to obtain rotational constants for the v = 0-2 levels of the a3Π state, using the Hamiltonian of Brown et al. (1979. J. M. Brown, E. A. Calbourn, J. K. G. Watson, and F. D. Wayne, J. Mol. Spectrosc. 74, 294-318). and the least squares formalism of Curl and Dane (1988. J. Mol. Spectrosc. 128, 406-412), as modified by Watson (1989. J. Mol. Spectrosc. 138, 302-308). Term values for the c3Π, v = 1 level have then been obtained from the line frequencies, and a set of effective rotational constants for the c3Π (v = 1) level of 13CO has been derived. © 2000 Academic Press.
Analysis of the A1П State on the Basis of the Douglas – Herzberg Bands System in the CH+ Ion Molecule.
(Polish Academy of Sciences, Institute of Physics (Acta Physica Polonica A), 2007-06) Hakalla, Rafał; Kępa, Rafał; Szajna, Wojciech; Zachwieja, Mirosław
This paper presents an attempt of examining the irregularities appearing in a complicated A1II state of the CH+ molecule with their reasons provided. By using the experimental data for the A1Π- X1Σ+ bands system of the 12CH+ ion radical, it was proved that the vibrational and rotational quanta of the upper state reveal the same unusual behaviour, i.e. very clear nonlinear dependence on vibrational quantum number (v′ ≥ 3) of the upper state. Therefore, upper vibrational levels (v′ ≥ 3) of the A1Π state cannot be determined by means of the equilibrium constants calculated in the previous works. Due to so far unidentified A1Π state perturbations, the reduction of the wave numbers to the rovibronic parameters was carried out by means of individual, band-by-band analysis method, using with this end in view the nonlinear least squares method introduced by Curl and Dane, and Watson. This method allowed one to make already calculated constants of the rovibronic structure of regular lower state X1Σ + of A-X system independent of possible perturbations appearing in the upper state of A1Π of this system. It also enabled one to calculate for the first time the real (perturbed) term values for the A 1Π (v′ = 0, 1, 2, and 3) state of the 12CH + ion molecule. These values suggest that rotational irregularities in the A1Π state examined are negligibly small, In order to confirm the nonexistence of rotational perturbations in the A1Π (v′ = 0, 1, 2, and 3) state, up to the observed Jmax level, appropriate graphs of functions fx(J) and gx(J) introduced by Gero and Kovács, where x = Q, PR, and PR, were drawn. Also, their course was analysed in detail.
Analysis of the c3Pi (v = 0, 1) State on the Basis of the 3A Band System in the 12C16O, 13C16O, and 14C16O Molecules
(2000 Academic Press (Journal of Molecular Spectroscopy), 2001) Hakalla, Rafał
The 1-0, 1-1, and 1-2 bands of the 3A system of 13CO (c3Π-a3Π) have been recorded for the first time, in the form of discharge emission spectra photographed at high resolution. Preliminary rotational analysis suggests that the v = 1 level of the c3Π state is perturbed in a fashion similar to the v = 0 level, previously observed by Dabrowski et al. (1987. I. Dabrowski, M. Vervolet, and D. C. Wang, Can. J. Phys. 65, 1171-1177). Rotational combination differences from the 1720 measured lines have been used to obtain rotational constants for the v = 0-2 levels of the a3Π state, using the Hamiltonian of Brown et al. (1979. J. M. Brown, E. A. Calbourn, J. K. G. Watson, and F. D. Wayne, J. Mol. Spectrosc. 74, 294-318). and the least squares formalism of Curl and Dane (1988. J. Mol. Spectrosc. 128, 406-412), as modified by Watson (1989. J. Mol. Spectrosc. 138, 302-308). Term values for the c3Π, v = 1 level have then been obtained from the line frequencies, and a set of effective rotational constants for the c3Π (v = 1) level of 13CO has been derived. © 2000 Academic Press.
Analysis of the c3 (v = 0, 1) State on the Basis of the 3A Band System in the 12C16O, 13C16O, and 14C16O Molecules.
(Academic Press (Journal of Molecular Spectroscopy), 2001) Hakalla, Rafał
Six bands of the 3A system (c 3Π-a 3Π) in the CO molecule have been photographed as an emission spectra by the Geissler tube. The conventional technique of spectroscopy has been implemented. It was the first attempt to analyze the 1-3 band in the 13C16O molecule as well as the 1-2 band in the 12C16O molecule at high resolution. The Th lines were used as a standard along with the interferometric comparator equipped with a photoelectric scanning device. The 0-2 and 0-3 bands in 12C16O and the 0-3 band in 13C16O and 14C16O were reanalyzed. The total number of lines studied within the framework of this project amounts to 3071. Due to complicated and not totally described perturbations which appeared in the upper state c 3Π(v = 0, 1), the effective rovibronic structure constants for this state were calculated (for the first time in the case of v = 1 level in the 12C16O). Global merging of the rotational constants of the a 3Π(v = 0, 1, 2, 3) and c 3Π(v = 0, 1) levels in 13C16O, as well as a 3Π(v = 2, 3) and c 3Π(v = 0, 1) in 12C16O, made it possible to obtain c 3Π vibrational differences Δv1-0 = 1742.0944 (22) cm-1 in 13C16O as well as 1775.7665 (41) cm-1 in 12C16O for the first time. The so far unknown band origins of the 0-v″ and 1-v″ progressions of the 3A system in the molecules under consideration have also been determined. The first attempt to specify the equilibrium molecular constants for the c 3Π state, along with the new values for the a 3Π state, on the basis of the obtained values of merged rovibronic constants has been undertaken. The vibrational constants of the c 3Π state in the 13C16O molecule as well as in the 12C16O molecule were thus obtained for the first time. The 1-2 band of 12C16O and Dunham's isotopic relationship were implemented for that purpose. The analysis of anomalously small values of the centrifugal distortion constant D of the c 3Π state and the global character of perturbations in the observed isotopes of the CO molecule suggest homogeneous interaction between c 3Π(v = 0, 1) and the k 3Π state. Simultaneously, the analysis of the comparatively large values of the Λ-doubling parameter q and the analysis of the shifts of the term values caused by perturbations presuppose a significant influence of a heterogeneous nature of any of the 3Σ states (most probably the j 3Σ+ state) on the c 3Π(v = 0, 1) state. The article also presents the first attempt to calculate RKR potentials, r-centroids, and Franck-Condon factors for the 3A system. © 2001 Academic Press.
Emission spectroscopy of AlH: the X1Σ+, A1Π and C1Σ+ states characteristics.
(Polish Academy of Sciences, Institute of Physics (Acta Physica Polonica A), 2011-09) Szajna, Wojciech; Zachwieja, Mirosław; Hakalla, Rafał; Kępa, Ryszard
The visible spectrum of AlH has been investigated at high resolution between 20000 and 21500 cm1 using a conventional spectroscopic technique. The AlH molecules were formed and excited in an aluminium hollow-cathode lamp with two anodes, filled with a mixture of Ne carried gas and a trace of NH 3. The emission from the discharge was observed with a plane grating spectrograph and recorded by a photomultiplier tube. The 0-0 and 1-1 bands of the C1Σ+-A1∏ system and 0-2 band of the A1∏-X1Σ+ were identified at 21126, 21368 and 20276 cm1, respectively. In total 121 transition wave numbers belonging to three bands were precisely measured (with accuracy of ±0.003 cm-1) and rotationally analysed. The new data were elaborated with the help of recent X1Σ+ state parameters reported by White et al. and of the C1Σ+, A1∏ states constants reported by Szajna and Zachwieja. As a result of this merged analysis the set of the molecular parameters and rotational terms values for the three lower lying states of the AlH molecule have been significantly improved.
Extended analysis of the Ångström band system (B1Σ+ - A1Π) in the rare12C17O isotopologue.
(IOP Publishing ( Journal of Physics B: Atomic, Molecular and Optical Physics), 2012-11) Hakalla, Rafał; Szajna, Wojciech; Zachwieja, Mirosław
The Ångström band system (B 1Σ + A 1Π), so far unobserved in the rare 12C 17O isotopologue, was obtained under high resolution as an emission spectrum using high accuracy dispersive optical spectroscopy. In total, 200 transition wave numbers belonging to the 0-1 and 0-2 bands were precisely measured and rotationally analysed. The obtained result was the merged rotational constants B 0 = 1.8988823(41)cm 1 and D 0 = 6.4283(26) × 10 6 cm 1 for the B 1Σ + Rydberg state as well as the individual rotational constants B 1 = 1.54088(12)cm 1, D 1 = 6.950(87) × 10 6cm 1, B 2 = 1.519292(69)cm 1, D 2 = 8.22(16) × 10 6cm 1 for the A 1Π state in the 12C 17O isotopologue. The band origins were also calculated. Numerous rotational perturbations observed in the A 1Π state in this molecule have been identified. The observed perturbations were confronted with those predicted from theoretical calculations. © 2012 IOP Publishing Ltd.
First analysis of the 1 – v’’ progression of the Ångström (B1Σ+ - A1Π) band system in the rare 13C17O isotopologue.
(ACS Publication (The Journal of Physical Chemistry A), 2013-11-27) Hakalla, Rafał; Szajna, Wojciech; Zachwieja, Mirosław
The 1-v″ progression of the Ångström band system, so far unobserved in the rare 13C17O isotopologue, was obtained under high resolution as an emission spectrum using a high accuracy dispersive optical spectroscopy. In the studied region 22 700-24 500 cm-1, 146 spectral lines were observed, among which 118 were interpreted as belonging to the 1-0 and 1-1 bands of B-A system, and the next 28 were interpreted as extra lines belonging to the 1-1 band of B1Σ+-e 3Σ- intercombination system, also unobserved in the 13C17O molecule so far. All those lines were precisely measured with an estimated accuracy better than 0.0025 cm-1, and rotationally analyzed. As a result the following in the 13C 17O molecule were calculated for the first time: the merged rotational constants B1 = 1.790 227(23) cm-1, D 1 = 6.233(47) × 10-6 cm-1, and ΔG1/2 = 2010.9622 (69) cm-1 and the equilibrium constants, ωe = 2076.04(57) cm-1, ωexe = 32.54(28) cm-1, Be = 1.824 678(15) cm-1, αe = 2.2967(24) × 10 -2 cm-1, De = 5.226(25) × 10-6 cm-1, and βe = 6.71(48) × 10-7 cm-1 for the B1Σ+ Rydberg state, as well as the individual rotational constant B0 = 1.504 85(78) cm -1, and the equilibrium constants ωe = 1463.340(21) cm-1, Be = 1.499 02(12) cm-1, αe = 1.778 2(49) × 10-2 cm-1, De = 7.36(56) × 10-6 cm-1 for the A 1Π state, and σe = 21 854.015(51) cm -1, RKR turning points, Franck-Condon factors (FCF), relative intensities, and r centroids for the Ångström band system. With the help of the strong and vast A1Π (v = 0) ∼ e 3Σ- (v = 1) interaction, the experimental parameters of the e3Σ- (v = 1) perturbing state were established in the 13C17O molecule for the first time. © 2013 American Chemical Society.
First analysis of the B1Σ+ (v=1) Rydberg state in the lesser-abundant 12C17O isotopologue on the basis of the 1 – v’’ progression of the Ångström band system.
(Elsevier (Journal of Quantitative Spectroscopy & Radiative Transfer), 2014-02) Hakalla, Rafał; Szajna, Wojciech; Zachwieja, Mirosław
So far unobserved in the 12C17O isotopologue, the 1-υ″ progression of the Ångström (B1σ+-A1Π) band system was recorded under high resolution in the 17,200-22,950cm-1 spectral region as an emission spectrum using high-accuracy dispersive optical spectroscopy. The 12C17O molecules were formed and excited in two steps in a stainless steel hollow-cathode lamp with two anodes. The emission from the discharge was observed with a plane-grating spectrograph and recorded by a photomultiplier tube.In the studied region, the full rotational structure of the 1-1 and 1-5 bands of the B-A system was observed, in total 114 spectral emission lines up to J″=21. All those lines were precisely measured with an estimated accuracy of about 0.0030cm-1, and rotationally analyzed. As a result, many molecular constants were determined for the B1σ+ and A1Π states in the 12C17O isotopologue. In this paper we have also presented the results of calculations concerning RKR turning points, Franck-Condon factors, relative intensities, and r-centroids for the Ångström band system in the 12C17O molecule. We have also determined the value of the δG1/2 vibrational quantum, the isotope shifts, as well as the main, isotopically invariant parameters of the B1σ+ Rydberg state in the CO molecule within the Born-Oppenheimer approximation.For the A1Π, υ=5 state, considerable irregularities of the rotational structure have been observed and analyzed in detail. Suspected candidates responsible for these perturbations have been identified. The B1σ+, υ=1 state has been thoroughly analyzed in terms of possible perturbations and it emerged to be completely regular in the 12C17O molecule up to the observed maximum J value. © 2014 Elsevier Ltd.
First analysis of the Herzberg (C1Σ+ - A1Π) band system in the less-abundant 13C17O isotopologue.
(The Royal Society of Chemistry, Cambridge (RSC Advances), 2014-09) Hakalla, Rafał
This work presents high-resolution emission spectra measurements of the Herzberg band system, which has not been observed and analysed in the 13C17O isotopologue so far. Bands C → A (0,1), (0,2) and (0,3) were recorded in a region at 22950-26050 cm-1 using high-accuracy dispersive optical spectroscopy. The 13C17O molecules were formed and excited in a stainless steel hollow-cathode lamp with two anodes. All 224 rovibrational spectra lines, up to Jmax = 30, were precisely measured with an accuracy of about 0.0030 cm-1 and rotationally analysed. In this work the following have been determined in 13C17O for the first time: the merged rotational constants of the C1Σ+(ν = 0) Rydberg state and the individual rotational constants of the A1Π(ν = 3) state, as well as the rotational and vibrational equilibrium constants for the C1Σ+ state, the band origins of the C → A system, the isotope shifts, and the ΔGC1/2 vibrational quantum. The combined analysis of the Herzberg bands obtained now and the Ångström (B1Σ+ → A1Π) system analysed earlier (R. Hakalla et al., J. Phys. Chem. A, 2013, 117, 12299 and R. Hakalla et al., J. Mol. Spectrosc., 2012, 272, 11) yielded a precisely relative characteristic of the C1Σ+(ν = 0) and B1Σ+(ν = 0 and 1) Rydberg states in the 13C17O molecule, among others νCB00, νCB01 vibrational quanta. Also, many molecular constant values of the C1Σ+ state in the 12C16O, 12C17O, 13C16O, 12C18O, and 13C18O isotopologues were determined, which have not been published so far, as well as the RKR turning points, Franck-Condon factors, relative intensities, r-centroids for the Herzberg band system and the main, isotopically invariant parameters of the C1Σ+ state in the CO molecule within the Born-Oppenheimer approximation. In the A1Π(ν = 3) state of the 13C17O molecule, extensive, multi-state rotational perturbations were found, which were analysed and substantiated in detail. The vibrational level ν = 0 of the C1Σ+ state was analysed, paying special attention to possible irregularities, and no noticeable perturbations were found in it up to the observed Jmax.
New analysis of the Douglas – Herzberg system (A1П – X1Σ+) in the CH+ ion radical.
(EDP Sciences, Springer-Verlag (The European Physical Journal D ), 2006-03-21) Hakalla, Rafał; Kępa, Ryszard; Szajna, Wojciech; Zachwieja, Mirosław
Three bands of the A1 ∏ -X1 σ+ system in the 12CH+ ion radical have been rephotographed under high resolution as an emission spectra using a Geissler-type discharge tube. The conventional technique of spectroscopy has been implemented. Using the Th lines as a standards, as well as an interferometric comparator equipped with a photoelectric scanning device, the 0-0, 0-1 and 2-1 bands have been reanalyzed. By means of much longer bands (Jmax = 17 in the Q(J) branch of the 0-0 band; Jmax = 16 in the R(J) branch of the 0-1 band; Jmax = 14 in the P(J) and Q(J) branches of the 2-1 band), than have been observed so far, as well as the merged calculations, using another five bands given by Carrington et al. [A. Carrington, D.A. Ramsay, Phys. Scripta 25, 272 (1982)] additionally, more accurate molecular constants for the X 1 σ+ state, the improved reduced band system origin Te = 24118.726 (14) cm-1 as well as for the first time the equilibrium molecular constants with their one standard deviation for the A1 ∏ state in the CH+ molecule have been computed: ωe′ = 1864.402(22), ωex e′ = 115.832(14), ωeye′ = 2.6301(24), Be′ = 11.88677(72), αe′e = 0.9163(18), γe′ = -2.29(12) × 10-2, εe′ = 4.95(20) × 10-3, D e′ = 1.92960(31) × 10-3, β e′= 1.0733(50) × 10-4, δ e′ = -1.312(16) × 10-5, qe′= 4.102(23) × 10-2, αqe′ = -3.14(16) × 10-3, and qDe′= -2.20(14) × 10 -5 cm-1. Only in our research the addition to the zero-point energy Y00′ = -1.9430 cm-1 and Y 00″ = 1.8953 cm-1 have been calculated. The equilibrium bond lengths of re′ = 1.235053(37) Å and re″ = 1.1308843(30) Å for the A1∏ and X1σ+ states, respectively have been computed. Full quantum-mechanics characteristic of the A-X bands system in the 12CH+ molecule, i.e. RKR turning points, the Franck-Condon factors and r-centroids have been obtained. Dissociation energies D e X1σ+ = (38470 ±3503) cm-1 and De A1∏ = (14415 ±3509) cm-1 for the molecule under consideration have been estimated.
Reanalysis of the Ångström System (B1Σ+ - A1Π) in the 13C16O Isotopic Molecule.
(Polish Academy of Sciences, Institute of Physics (Acta Physica Polonica A), 2012-10) Hakalla, Rafał; Szajna, Wojciech; Zachwieja, Mirosław; Kępa, Ryszard
The emission spectrum of the Ångström system (B 1 Σ+-A 1π) of 13C 16O was obtained under high resolution with an accuracy estimated to be ±0:002 cm -1 as an emission spectrum using a high accuracy dispersive optical spectroscopy. The light source was a hollow-cathode lamp with two anodes built in our laboratory, with a previously deposited small quantity of 13C carbon on the electrodes. The emission from the discharge was observed with a plane grating spectrograph and recorded by a photomultiplier tube. In total 195 transition wave numbers belonging to the strongest 0-1 and 0-2 bands of the B-A system were precisely measured. The modern rotational reanalysis made it possible to verify the molecular information for the both combining states of the Ångström system. In particular the rovibrational constants for the B 1Σ + Rydberg state have been significantly improved (B0 = 1:8625054(65) cm -1 and D 0 = 6:1384(52) × 10 -6 cm -1) and the obtained equilibrium rotational constants of this state are more accurate than known to date. Numerous rotational perturbations observed in the A 1π state were reanalysed and confronted with the previously known ones.
The 3A Band System in the Spectrum of the 13C16O Molecule.
(Academic Press (Journal of Molecular Spectroscopy), 1999) Hakalla, Rafał; Kępa, Ryszard; Rytel, Marek; Zachwieja, Mirosław
In the emission spectrum of the carbon monoxide 13C16O isotopic molecule three bands comprising about 1820 lines of the 3A band system (c3Π-a3Π) were recorded and analyzed. The 0-0 and 0-1 bands of this system were photographed for the first time and the 0-2 band was rephotographed by using methods of conventional high-resolution spectroscopy. The result of the rotational band analysis includes expanding of the spectrum interpretation up to J = 25 as well as the identification of four previously unobserved branches P13, R13, P31, and R31. Because of strong perturbations in the c3Π (ν = 0) state, the calculation of the rovibronic structure constants was performed only for the lower a3Π state. By using a calculation based on a nonlinear least-squares method, an effective Hamiltonian of Brown [J. M. Brown, E. A. Colbourn, J. K. G. Watson, and F. D. Wayne, J. Mol. Spectrosc. 74, 294-318 (1979)] and a separative procedure proposed by Curl-Dane-Watson [R. F. Curl and C. B. Dane, J. Mol. Spectrosc. 128, 406-412 (1988); J. K. G. Watson, J. Mol. Spectrosc. 138, 302-308 (1989)], it was possible to derive the rotational structure constants for the ν = 0, 1, and 2 levels for the a3Π state in the 13C16O isotopic molecule. Term values for the C3Π (ν = 0) level and the equilibrium molecular constants for the a3Π state also are reported. © 1999 Academic Press.
The Ångström (B1Σ+ - A1Π) 0 – 1 and 1 – 1 bands in isotopic CO molecules: further investigations.
(IOP Publishing ( Journal of Physics B: Atomic, Molecular and Optical Physics), 2014-02-28) Kępa, Ryszard; Ostrowska-Kopeć, Małgorzata; Piotrowska, Izabela; Zachwieja, Mirosław; Hakalla, Rafał; Szajna, Wojciech; Kolek, Przemysław
In the emission spectrum of six 12C16O, 13C16O, 12C18O, 14C 16O, 13C18O and 14C18O isotopologues of the carbon monoxide molecule, new recordings and analyses or new reanalyses of the selected and strongest bands belonging to the Ångström (B1Σ+ - A1Π) system were carried out. Under high resolution, emission spectra of the 0-1 and 1-1 bands were recorded and reanalysed, representing both the 0 - v″ and 1 - v″ progressions of this system. Unobserved so far, new spectral lines were identified, and for the 12C16O, 13C 16O, 12C18O, 14C16O and 14C18O molecules new parameters of the rovibronic structure B0, B1, D0 and D1 of the v = 0 and v = 1 levels of the B 1Σ+ state and band origins ν0 of the 0-1 and 1-1 bands of the B - A transition were determined. A detailed analysis included the predissociation regions of the spectra observed in all analysed bands and isotopologues. The values of rotational quantum numbers and rovibronic terms of the highest nonpredissociated Jh as well as the first, already predissociated Jf levels were determined. On that basis, a new and more precise value of dissociation energy of the CO molecule was determined: cm-1. Also, atomic states of the dissociation products of this molecule, which correspond to this energy, were identified as C(3P0) + O(3P2) i.e. as both triplet ground atomic sublevels. © 2014 IOP Publishing Ltd.