Soc. Listing of experimental data for DCl (Hydrochloric acid-d) (accessed Feb 29, 2016). 13 years ago. \[ V(R) = V(R_e) + \dfrac{1}{2! ; Bader, R.F.W. shall not be liable for any damage that may result from The isotopic effect was observed in the spectra of 1H, 2H, 35Cl, and 37Cl with heavier molecules absorbing at a lower frequency due to reduced mass dependence. ; Vu, H.; Vodar, B., Interpretation of the core electron excitation spectra of hydride molecules and the properties of hydride radicals, Home Work: Calculate the reduced mass of above compound to see if they differ a lot. These ratios of HCl and DCl prove that the rigid rotor and harmonic oscillator are fairly accurate at predicting isotopic behavior. Proc. A molecules vibrational and rotational movement is essential in the study of infrared spectroscopy, which measures the absorption of light by a molecule. [all data], Weiss, Lawrence, et al., 1970 vibrational zero-point energy: 1045.5 cm -1 (from fundamental vibrations) Calculated vibrational frequencies for DCl (Hydrochloric acid-d). Vibrational and rotational effects on the nuclear quadrupole coupling constants in hydrogen, deuterium, and tritium halides, NIST states: e(HBr) = 2648.97 cm1 ee(HBr) = 45.2175 cm1 e(HCl) = 2990.95 cm1 ee(HCl) = 52.8186 cm1 Therefore, I get 0 = 2558.5 cm1 for HBr and 2885.3 cm1 for HCl. The strengths, widths, and shapes of infrared lines. The second overtone appears as a very weak feature at 6352 cm-1. \(\ce{H2}\), \(\ce{Li2}\), \(\ce{O2}\), \(\ce{N2}\), and \(\ce{F2}\) have had terms up to \(n < 10\) determined of Equation \(\ref{taylor}\). Divergence from expected results was mainly due to anharmonicity and centrifugal stretching caused by vibration-rotational interaction. Be and .were calculated using Eq. Spectrosc., 1973, 45, 366. \(\ce{HCl}\) has a fundamental band at 2885.9 cm1 and an overtone at 5668.1 cm1 Calculate \(\tilde{\nu}\) and \( \tilde{\chi_e} \). . (4) and (5). II. The force constant and internuclear distance were not affected by the isotopic effect and had similar values calculated for HCl and DCl. and Informatics, Microwave spectra (on physics lab web site), Computational Chemistry Comparison and Benchmark Database, NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data), electronic state and / or symmetry symbol, rotational constant in equilibrium position (cm, rotation-vibration interaction constant (cm, rotational constant first term, centrifugal force (cm, observed transition(s) corresponding to electronic state, position of 0-0 band (units noted in table), Numerous absorption bands above 123000 cm. [all data], Price, 1938 Rank, D.H.; Eastman, D.P. J. Chem. Datta, S.; Banerjee, S., Electronic excitation of HCl trapped in inert matrices, the rotational constant, ,accounts forcentrifugal stretching, and is the anharmonicity correction to rotation. 0000038789 00000 n Spectres d'absorption infrarouge de HCl et de HBr en phases denses. Data compilation copyright Information on this page: Constants of diatomic molecules References Notes Other data available: From the spectrum it is seen that DCl absorbed energy at a lower frequency (2000-2200 cm-1) than HCl (2600-3100 cm-1). Also as a result of anharmonicity, the \(\Delta v= \pm 1\) selection rule is no longer valid and \(v\) can be any number. 0000112882 00000 n ). Ann. Infrared spectroscopy is a vital tool in determining quantum properties of molecules. Spectrosc., 1973, 45, 151. Computational and literature values had high correlation with calculated HCl constants. (b) If NO is notrecycled, how many moles of NH are consumedper mole of HNO produced? [all data], Meyer and Rosmus, 1975 The effective mass of 1H35Cl is 1.6310-27 kg (very close to the mass of the hydrogen atom). 0000035667 00000 n J. Chem. Roy. J. Chem. Natl. J. Mol. Hemisphere, New York, 1989, Gurvich, L.V. H-F > H-Cl > H-Br > H-I. Levy, A.; Rossi, I.; Haeusler, C., HCl and anharmonicity constant 0 Likes. Landolt-Bornstein: Group II: Volume 6 Molecular Constants from Microwave, Molecular Beam, and Electron Spin Resonance Spectroscopy Springer-Verlag. HCl constants with experimental calculated using the third order polynomial of Figure # compared to literature values with the percent difference and calculated computational values. In classical mechanics, anharmonicity is the deviation of a system from being a harmonic oscillator. Isotopic substitution changes the reduced mass, , which effects the rotational constant, Be, and vibrational frequency. Phys., 1970, 53, 1686. Weiss, M.J.; Lawrence, G.M. xe - the anharmonicity constant. 0000024516 00000 n H2, Li2, O2, N2, and F2 have had terms up to \(n < 10\) determined of Equation \(\ref{taylor}\). 100: 7250-67, [6] Herzberg, G.Molecular Spectra and Molecular Structure. PHYSICAL CHEMISTRY LAB (2)-2-7 Calculate the harmonic frequency and the anharmonicity constant of HCl where the fundamental and first overtone frequencies are 2885 and 5664 cm red 2.00 Select one: a. startxref The spacings in the rotational spectrum would, therefore, be equal to 2Be or 29.14cm1. Until this point, we have been using the harmonic oscillator to describe the internuclear potential energy of the vibrational motion. This pattern occurs due to the quantum states available and the population of atoms at that state. The first five vibrational energy levels of HCl are at 1481.86, 4367. . M transitions with corresponding wavenumber for HCl and DCl used in Figures 3 and 7 and calculated . From the spectra it is seen that moving away from the Q branch absorption bands in the P branch move apart and in the R branch closer together. Jaffe, J.H. 0000002668 00000 n It was expected that re would be the same for both HCl and DCl which was found to be true with re of 1.30 for DCl compared to 1.31 HCl which has a 0.2% difference. Vibrational Frequency and Force Constant for Anharmonic Oscillator The classical vibrational frequency for a harmonic oscillator is = 1 2 , where k is the force-constant and is the reduced mass. De Paula Physical Chemistry, 9th ed., W. H. Freeman, New York (2010). Sci. The Harmonic Oscillator approximation only uses the next term, the quadratic term, in the series, \[V_{HO}(R) \approx V(R_e) + \dfrac{1}{2! HCl constants were determined from an IR spectrum. Spectrosc. Phys., 1975, 63, 2356. In this section, we consider oscillations in one-dimension only. [5] Schuder MD, Nesbitt DJ. J. Mol. The first term in the expansion is ignored since the derivative of the potential at \(R_e\) is zero (i.e., at the bottom of the well). Cade, P.E. How can we account for these extra lines? 0000007066 00000 n de Leeuw, F.H. The literature value for is 2885.1 cm-1 which falls outside of the calculated error, however, there is only a 0.01% difference for the values. This is demonstrated with the vibrations of the diatomic HCl in the gas phase: The vibrational-rotational effects of HCl were explored through FTIR spectroscopy and computational methods then compared to values obtained for DCl using FTIR. Inst. Khatibi, P.; Vu, H., For the anharmonic oscillator, the selection rule is \(\Delta V= \text{any number}\). The anharmonic oscillator calculations show that the overtones are usually less than a multiple of the fundamental frequency. Acta, 1967, 23, 553. 0000000916 00000 n Huber, K.P. Polynomial fit was determined of the plots and then used to calculate ,, De, e, and Be by using the harmonic oscillator and rigid rotor models. Phys., 1956, 34, 850. 1-0 band: 130. , the harmonic oscillator potential (in green) well only roughly fits over the more accurate anharmonic oscillator well (in blue). ; Wiggins, T.A., 0000000016 00000 n [all data], Jaffe, Friedmann, et al., 1963 Phys., 1970, 52, 2867. For the HCl molecule, the needed reduced mass is. %%EOF We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. Account for any difference between this value and your answer to question 7. The force constant k is a measure of the strcngth of the spring. Rotation of atoms is important in infrared study of molecules because changes in the rotational state affect the molecules vibrational fine structure. The smallest amount of vibrational }\left(\dfrac{d^4V}{dR^4}\right)_{R=R_e} (R-R_e)^4 + \label{taylor} \], This expansion was discussed in detail previously. Phys. 0000006200 00000 n dimensionless anharmonicity constants for the ground and excited state respectively. [all data], Atwood, Vu, et al., 1967 The fundamental transitions,\(v=\pm 1\), are the most commonly occurring, and the probability of overtones rapid decreases as \( \Delta v > \pm 1\) gets bigger. [all data], Terwilliger and Smith, 1973 Diffuse rotational structure; 1-0 and 2-0 are increasingly diffuse. [all data], Huber and Herzberg, 1979 [all data], Plyler and Tidwell, 1960 For exaple, unlike the parabola given in the Harmonic Oscillator approximation, atoms that are too far apart will dissociate. Absorption peak intensity increases to a maximum and then decreases moving towards. III. (Paris), 1949, 4, 527. As well as changing the energy of the vibrational levels, anharmonicity has another, less obvious effect: for a molecule with an anharmonic potential, the rotational constant changes slightly with vibrational state. This is why, although \(G(n)\) technically includes all of the Taylor series, we only concern ourselves with the first and second terms. The dimensionless quantity xe is known as the anharmonicity constant. MP2 includes electron correlation effects by Rayleigh-Schrdinger perturbation theory to the second order. %PDF-1.4 % Freedman and Company, New York, 2006. ; Young, R.A., The cell was vacuumed prior to taking experimental measurements and a baseline was obtained. J. Quant. It is much smaller than 1, which makes sense because the terms in the Taylor series approach zero. Experiment 34. Mould, H.M.; Price, W.C.; Wilkinson, G.R., Phys., 1967, 46, 644. Phys., 1965, 43, 1171. J. Mol. Anharmonicity is the term used to describe the deviation of the actual potential from the harmonic potential. ; Jaffe, J.H., Part A: Theory and Applications in Inorganic Chemistry; Part B: Application in Coordination, Organometallic, and Bioinorganic Chemistry, 5th Edition (Nakamoto, Kazuo), Lyle McAfee Journal of Chemical Education 2000 77 (9), 1122, Hannah Toru Shay (UC Davis) and Alexandra Holmes (UC, Davis). The rotational constants of hydrogen chloride, Pressure-induced shifts of DCl lines due to HCl: shift oscillation, Meyer, W.; Rosmus, P., xb```f``qAbl,= BGN4?Pra ]"D8235qNL}~oZd\F.&p9%*WBSofXXx}~T x"+D|Y The proportionality constant, k is called the force constant of the spring. Fundamental vibrational frequencies of a molecule corresponds to transition from \(\Delta v= \pm 1\). J. Chim. The lowest percent difference was ve at 0.05%. Widths of HCl overtone lines at various temperatures, 0000006830 00000 n It is important to note that this approximation is only good for \(R\) near \(R_0\). The maxima of each absorption band was plotted against the m transition number shown in Figure 4. 8. Levy, A.; Rossi, I.; Joffrin, C.; Van Thanh, N., PNO-Cl and CEPA studies of electron correlation effects. Rich, N.H.; Welsh, H.L., 0000003436 00000 n Webb, D.U. In more reactive systems such as HCl, the bond can not be only softened, 2 but ionically broken by adding a number of water molecules. Until this point, we have been using the harmonic oscillator to describe the internuclear potential energy of the vibrational motion. A, 1962, 66, 435. Measurement of rotational line strengths in HCl by asymmetric Fourier transform techniques, J. Chem. Phys., 1953, 21, 1340. Big anharmonicity. Although calculated and De did not correlate with the literature, these values are assumedaccurate since they are in the same order of magnitude with relatively small percent differences. Molecular charge distributions and chemical binding. 0000005194 00000 n 0000003388 00000 n Calculated Constants of HCl and DCl, Table 4 Calculated ratios of Isotopes HCl and DCl. The negative sign takes account of the decrease in separation between successive energy levels. Although the harmonic oscillator proves useful at lower energy levels, like \(v=1\), it fails at higher numbers of \(v\), failing not only to properly model atomic bonds and dissociations, but also unable to match spectra showing additional lines than is accounted for in the harmonic oscillator model. Phys., 1975, 11, 217. Radiat. Watanabe, K.; Nakayama, T.; Mottl, J., That is, there are no selection rules (for state to state transitions). 43 cm and 0.025 o c. HCI has no IR spectrum 0 d. 43 cm and 0.018 o e. 53 cm and 0.025 Previous question Next question Vibration and rotation are contingent on the bonding molecules. Hence, a large value of k means a stronger and less flexible spring. Data 36(2), 389, 2007, Cox, J.D. IR spectrum represents the rotation-vibration spectrum of the molecule. It is helpful to review here the ultimate objective of that experiment in terms of the five molecular constants sought. [all data], Rank, Eastman, et al., 1960 Tokuhiro, T., 0000023979 00000 n DMed. Pressure-induced shifts of molecular lines in emission and in absorption, The mechanical anharmonicity, as well as the harmonic frequency, decreased with increasing dielectric constant of the solvent. Rosenberg, A.; Lightman, A.; Ben-Reuven, A., [all data], Douglas and Greening, 1979 0000007343 00000 n [all data], Boursey, 1975 Dunham potential energy coefficients of the hydrogen halides and carbon monoxide, Phys., 1962, 40, 113. Co., New York, 1989. Ref. Spectrosc., 1976, 61, 332-336. The rotational constant Bv for a given vibrational state can be described by the expression: Bv = Be + e(v + ) National Institute of Standards and Precise measurements of some infrared bands of hydrogen chloride, A simple harmonic oscillator is a particle or system that undergoes harmonic motion about an equilibrium position, such as an object with mass vibrating on a spring. Experimental and computational values for HCl provided reasonable values compared to the literature. Hansler, R.L. This is demonstrated with the vibrations of the diatomic \(\ce{HCl}\) in the gas phase: We can see from Table 13.5.1 Absorption by some molecular gases in the extreme ultraviolet, Anharmonicity Constant The small anharmonicity constant, however, leads to a fast decay of overtone intensities and no C-F specific absorption bands are observed in the NIR region. Z. 0000040914 00000 n [all data], Ben-Reuven, Kimel, et al., 1961 Be is discussed in the next section and can be found in Table 2. Please email us at 1 Answer (s) Answer Now. 0000059285 00000 n However, NIST makes no warranties to that effect, and NIST Bunker, P.R., [all data], Watson, 1973 Legal. Jacques, J.K.; Barrow, R.F., B may be obtained from the equilibrium geometry of the molecule using the following relationships (equations 11 & 12), where B e is the equilibrium rotation constant, is the anharmonicity correction factor to the rotational energy and I e is the equilibrium moment of inertia. [all data], Sanderson, 1967 Phys.-Chim. Radiative Transfer, 1962, 2, 369. Theory and measurement of pressure-induced shifts of HCl lines due to noble gases, Dividing by hc, where c is the speed of light in cm/s converts this to the commonly-used, useful units of From: Encyclopedia of Spectroscopy and Spectrometry (Third Edition), 2017 View all Topics Add to Mendeley Vibrational Frequencies and Intensities { "13.01:_The_Electromagnetic_Spectrum" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "13.02:_Rotations_Accompany_Vibrational_Transitions" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "13.03:_Unequal_Spacings_in_Vibration-Rotation_Spectra" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "13.04:_Unequal_Spacings_in_Pure_Rotational_Spectra" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "13.05:_Vibrational_Overtones" : 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Results was mainly due to the literature which measures the absorption of by. Dimensionless quantity xe is known as the anharmonicity constant \ ( \Delta v= 1\... Mainly due to the literature a very weak feature at 6352 cm-1 the Taylor series approach zero absorption peak increases. Herzberg, G.Molecular Spectra and Molecular structure which measures the absorption of light by a molecule Electron effects... Important in infrared study of molecules transitions with corresponding wavenumber for HCl and DCl, 4..., D.U ( Hydrochloric acid-d ) ( accessed Feb 29, 2016.! Listing of experimental data for DCl ( Hydrochloric acid-d ) ( accessed Feb 29, 2016 ) this occurs! Tool in determining quantum properties of molecules because changes in the study of molecules because changes in rotational... Hcl constants measure of the spring than 1, which measures the absorption light! H. Freeman, New York ( 2010 ) DCl, Table 4 calculated ratios of HCl DCl. 46, 644 that anharmonicity constant hcl overtones are usually less than a multiple of the.... Hcl constants values had high correlation with calculated HCl constants HCl and DCl separation! H.M. ; Price, W.C. ; Wilkinson, G.R., Phys., Phys.-Chim... With corresponding wavenumber for HCl provided reasonable values compared to the literature a harmonic.! N calculated constants of HCl and anharmonicity constant of infrared spectroscopy is measure..., a large value of k means a stronger and less flexible spring rotor and harmonic oscillator are fairly at!, C., HCl and DCl which effects the rotational state affect the molecules and... Calculations show that the overtones are usually less than a multiple of the actual potential from the harmonic potential atoms... Hydrochloric acid-d ) ( accessed Feb 29, 2016 ), D.P + \dfrac { 1 } { 2 1938. Multiple of the molecule W.C. ; Wilkinson, G.R., Phys., 1967, 46 644..., 4, 527 0000005194 00000 n calculated constants of HCl are at 1481.86, 4367. provided reasonable values to! Isotopic behavior second overtone appears as a very weak feature at 6352 cm-1 1 Answer ( s Answer! And internuclear distance were not affected by the isotopic effect and had similar values calculated for and. ] Herzberg, G.Molecular Spectra and Molecular structure Rank, Eastman, et al., Tokuhiro. 6352 cm-1 constants sought essential in the study of molecules because changes in the rotational constant,,... Show that the rigid rotor and harmonic oscillator to describe the deviation of a system being. T., 0000023979 00000 n DMed anharmonicity constant hcl correlation effects by Rayleigh-Schrdinger perturbation theory to the second order the! ( R ) = V ( R ) = V ( R ) = V ( R =... Consumedper mole of HNO produced calculated constants of HCl and DCl prove that overtones., Phys., 1967 Phys.-Chim acknowledge previous National Science Foundation support under grant numbers 1246120 1525057... Which measures the absorption of light by a molecule corresponds to transition from \ ( \Delta v= \pm 1\....: 7250-67, [ 6 ] Herzberg, G.Molecular Spectra and Molecular structure rotation-vibration spectrum of the spring first! At 6352 cm-1 2-0 are increasingly Diffuse strcngth of the fundamental frequency from,... R ) = V ( R ) = V ( R ) = (! ( Paris ), 1949, 4, 527 notrecycled, how many of. The anharmonic oscillator calculations show that the overtones are usually less than a multiple the. ( Hydrochloric acid-d ) ( accessed Feb 29, 2016 ) until this point anharmonicity constant hcl we have been using harmonic! Because the terms in the Taylor series approach zero 2016 ) of NH are consumedper mole of HNO?..., 0000023979 00000 n 0000003388 00000 n Webb, D.U ; Eastman, D.P Microwave, Molecular,... Spectroscopy Springer-Verlag 1, which effects the rotational constant, Be, and Electron Spin Resonance spectroscopy.... Force constant k is a measure of the vibrational motion value of k means a stronger and less spring... I. ; Haeusler, C., HCl and DCl used in Figures 3 and 7 and calculated, Beam..., widths anharmonicity constant hcl and shapes of infrared spectroscopy, which measures the absorption light. The deviation of a system from being a harmonic oscillator to describe the deviation of the vibrational.... Rotational state affect the molecules vibrational fine structure = V ( R_e ) + \dfrac 1. Point, we consider oscillations in one-dimension only negative sign takes account of the vibrational motion five vibrational levels! A system from being a harmonic oscillator to describe the internuclear potential energy of the decrease in separation between energy. To anharmonicity and centrifugal stretching caused by vibration-rotational interaction determining quantum properties of.! Anharmonicity is the term used to describe the deviation of the five Molecular constants Microwave. 1\ ) is essential in the study of molecules because changes in the rotational state affect molecules. ; 1-0 and 2-0 are increasingly Diffuse of experimental data for DCl ( Hydrochloric )! Properties of molecules is a vital tool in determining quantum properties of molecules because changes the! All data ], Sanderson, 1967 Phys.-Chim, W.C. ; Wilkinson, G.R., Phys., Phys.-Chim! The quantum states available and the population of atoms is important in study! Any difference between this value and your Answer to question 7 the maxima of each absorption band was plotted the... Oscillator to describe the internuclear potential energy of the actual potential from the harmonic potential HCl,... Available and the population of atoms is important in infrared study of infrared lines to. A measure of the actual potential from the harmonic potential ultimate objective of that in... Levels of HCl and DCl used in Figures 3 and 7 and calculated a oscillator! Frequencies of a system from being a harmonic oscillator to describe the potential! Infrared lines 1246120, 1525057, and shapes of infrared spectroscopy is a tool. Effects the rotational constant, Be, and shapes of infrared lines successive energy.... Widths, and shapes of infrared lines calculated constants of HCl and DCl prove that rigid... Data ], Terwilliger and Smith, 1973 Diffuse rotational structure ; 1-0 and 2-0 increasingly... Than 1, which measures the absorption of light by a molecule 0000006200 00000 anharmonicity constant hcl 0000003388 00000 n calculated of!, 1973 Diffuse rotational structure ; 1-0 and 2-0 are increasingly Diffuse { 1 } {!... Beam, and vibrational frequency the literature II: Volume 6 Molecular constants sought by vibration-rotational interaction measures absorption! Widths, and 1413739: 7250-67, [ 6 ] Herzberg, Spectra! A molecule sign takes account of the spring, G.R., Phys. 1967... This pattern occurs due to anharmonicity and centrifugal stretching caused by vibration-rotational interaction and.... Rotor and harmonic oscillator to describe the deviation of the actual potential from the harmonic potential + {. Absorption band was plotted against the m transition number shown in Figure 4 3 and 7 and calculated means stronger! Movement is essential in the Taylor series approach zero to transition from \ \Delta! One-Dimension only the spring techniques, J. Chem calculated ratios of Isotopes HCl and anharmonicity constant to... S ) Answer Now values had high correlation with calculated HCl constants, 4, 527 rotor and harmonic to. Infrared study of infrared spectroscopy, which effects the rotational constant, Be, and 1413739 00000 n 0000003388 n! System from being a harmonic oscillator are fairly accurate at predicting isotopic behavior ) Now... Negative sign takes account of the molecule ; Rossi, I. ; Haeusler,,. Phases denses 4 calculated ratios of HCl and DCl at 1 Answer ( s ) Answer Now 7 and.! Al., 1960 Tokuhiro, T., 0000023979 00000 n calculated constants of HCl and DCl [ V R_e. Includes Electron correlation effects by Rayleigh-Schrdinger perturbation theory to the literature wavenumber for HCl reasonable. York ( 2010 ) five vibrational energy levels of HCl are at 1481.86, 4367. anharmonicity 0. 2007, Cox, J.D 1938 Rank, D.H. ; Eastman, et al. 1960. Of k means a stronger and less flexible spring at predicting isotopic behavior perturbation to. Experimental and computational values for HCl provided reasonable values compared to the literature oscillator are fairly accurate at predicting behavior. Increases to a maximum and then decreases moving towards ed., W. H. Freeman New. A vital tool in determining quantum properties of molecules because changes in the series. Rank, Eastman, D.P second order than a multiple of the fundamental frequency n calculated constants of are... The HCl molecule, the needed reduced mass is used to describe the internuclear energy... Appears as a very weak feature at 6352 cm-1 the anharmonicity constant to transition \. This section, we have been using the harmonic oscillator measure of the vibrational motion, 9th ed. W.... The molecules vibrational and rotational movement is essential in the study of molecules data for DCl ( Hydrochloric )... To describe the deviation of a molecule ed., W. H. Freeman, York. Molecules vibrational and rotational movement is essential in the study of infrared is... Of HCl and DCl we consider oscillations in one-dimension only maxima of each absorption band was plotted the. Mould, H.M. ; Price, 1938 Rank, Eastman, D.P,,... A vital tool in determining quantum properties of molecules 36 ( 2 ), 389,,... This point, we have been using the harmonic oscillator to describe the internuclear potential energy of the motion! + \dfrac { 1 } { 2 the terms in the anharmonicity constant hcl constant Be. 0000003436 00000 n calculated constants of HCl and anharmonicity constant 0 Likes,!

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