Showing papers in "Canadian Journal of Physics in 1975"
TL;DR: In this paper, the radio frequency and microwave spectrum of KrClF has been measured by molecular beam electric resonance spectroscopy and the molecular constants for the major isotope (84Kr35ClF) are:The atomic arrangement is KrCl-F with a linear equilibrium structure and the vibrationally averaged 84Kr-35Cl distance is 3.3884
Abstract: The radio frequency and microwave spectrum of KrClF has been measured by molecular beam electric resonance spectroscopy. The molecular constants for the major isotope (84Kr35ClF) are:The atomic arrangement is Kr—Cl—F with a linear equilibrium structure and the vibrationally averaged 84Kr—35Cl distance is 3.3884 A. The molecular structure is very similar to that of ArClF, previously studied in this laboratory. Vibrational frequencies, force constants, estimated well depths, dipole moments, and distances in the two molecules are compared. Molecular constants of the four KrClF isotopes studied are used to derive a vibrational force field for the molecule, including anharmonic and bend–stretch coupling terms. A brief summary of the four linear van der Waals molecules studied spectroscopically in this laboratory is presented, along with a simple and structurally predictive model of the van der Waals bond.
154 citations
TL;DR: The density functional theory of Hohenberg, Kohn, and Sham has been used to derive an exact variational expression for the spin susceptibility (χ) of an inhomogeneous electron gas as discussed by the authors.
Abstract: The density functional theory of Hohenberg, Kohn, and Sham has been used to derive an exact variational expression for the spin susceptibility (χ) of an inhomogeneous electron gas. This variational...
137 citations
TL;DR: The band systems of HCO and DCO have been reinvestigated with higher resolving power than in earlier work as mentioned in this paper, and some weak lines have been assigned to K′"="0 − K" and K''" ="0 - K" subbands.
Abstract: The band systems of HCO and DCO have been reinvestigated with higher resolving power than in earlier work. Some weak lines have been assigned to K′ = 0 – K″ = 0 and K′ = 0 – K″ = 2 subbands; these ...
121 citations
TL;DR: In this article, an attempt was made to measure the absorption cross sections of O2 in the metastable state a1Δg from 1087 to 1700 ǫ A.
Abstract: An attempt has been made to measure the absorption cross sections of O2 in the metastable state a1Δg from 1087 to 1700 A. The absorption is measurable (σa ≥ 3 × 10−19 cm2) from around 1500 A toward...
113 citations
TL;DR: In this paper, the microwave and millimetre wave spectra of six isotopic species of isocyanic acid, HNCO, have been measured using a very slightly asymmetric prolate rotor.
Abstract: The microwave and millimetre wave spectra of six isotopic species of isocyanic acid, HNCO, have been measured. The molecule is a very slightly asymmetric prolate rotor. Besides the a type R branche...
104 citations
TL;DR: In this paper, the molecular beam electric resonance method was employed to obtain a complete set of hyperfine Λ doubling transitions of the free radicals OH, OD, SH, and SD.
Abstract: The molecular beam electric resonance method was employed to obtain a complete set of hyperfine Λ doubling transitions of the free radicals OH, OD, SH, and SD. The observed spectra could be explain...
94 citations
TL;DR: In this paper, the transition probabilities of the 5577 A and 6300 A lines of [OI] were obtained by simultaneously measuring the absolute intensity and the population of the upper state of each line in an inert gas-oxygen discharge.
Abstract: We have obtained the transition probabilities of the 5577 A, and 6300 A lines of [OI] by simultaneously measuring the absolute intensity and the population of the upper state of each line in an inert gas–oxygen discharge. Further, we have obtained A values for the 2972 A and 6364 A lines by measuring relative intensities of lines from the 1S0 and 1D2 levels.
93 citations
TL;DR: The electronic spectrum of calcium vapor has been photographed in absorption from 460 to 600 nm as discussed by the authors, and a many line spectrum due to Ca2 has been identified from vibrational and rotational analyses and a t...
Abstract: The electronic spectrum of calcium vapor has been photographed in absorption from 460 to 600 nm. A many line spectrum due to Ca2 has been identified from vibrational and rotational analyses and a t...
88 citations
TL;DR: In this paper, accurate measurements of the Abraham density force have been conducted in a BaTiO3 ceramic for the first time, which conclusively rules out Minkowski's unsymmetric momentum energy tensor for material media at low frequencies.
Abstract: Accurate measurements of the Abraham density force have been conducted in a BaTiO3 ceramic for the first time. The measured torque amplitudes (in the order of 10−10 Nm) were in good agreement with the predicted values inside the error limits of 10%. This conclusively rules out Minkowski's unsymmetric momentum-energy tensor for material media at low frequencies.
86 citations
TL;DR: In this article, the A3Πi−X3Σ−− emission systems of OD+ and OH+ have been investigated in detail, and accurate rotational constants have been obtained for all the bands.
Abstract: The A3Πi–X3Σ− emission systems of OH+ and OD+ have been reinvestigated in detail. Fourteen bands have been analyzed (of which seven are new), and accurate rotational constants have been obtained fo...
82 citations
TL;DR: The energy spectra of 1'MeV He+ ions backscattered from single crystals of Al alloys containing 0.03'at.% Sn have been examined in different crystallographic directions as mentioned in this paper.
Abstract: The energy spectra of 1 MeV He+ ions backscattered from single crystals of Al alloys containing 0.09 at.% Mn, 0.09 at.% Zn, 0.08 at.% Ag, or 0.03 at.% Sn have been examined in different crystallographic directions. For the annealed crystals, the minimum yield of back-scattered He+ ions from Al atoms at 40 K in a direction was , and the corresponding yield from Mn, Zn, or Ag impurity atoms was (χmin)i ≤ 0.06, indicating that at least 96% of these impurity atoms had replaced Al atoms at normal lattice sites. For the Al–0.03 at.% Sn alloy, the substitutional fraction of Sn atoms was only ~50% for a slowly cooled crystal, but was increased to ~90% by a rapid (water) quench from 600 °C. Irradiation of the crystals at 40–70 K with 0.3–1.0 MeV He+ ions to doses of 1015–1016/cm2 caused the Mn, Zn, and Ag atoms to be displaced from lattice sites by the trapping of self-interstitial Al atoms. From an analysis of , , {100}, and {111} channeling, it was shown that the trapping configuration was the dumbbell. Both the...
TL;DR: In this article, rotational analyses have been carried out, with varying degrees of completeness, for nine bands of O2 and two bands of S18O2 in the region 3000-3300 A.
Abstract: Rotational analyses have been carried out, with varying degrees of completeness, for nine bands of S16O2 and two bands of S18O2 in the region 3000–3300 A. The bands are all highly perturbed type C ...
TL;DR: In this article, the and transitions of the CO2+ ion were photographed in emission under high spectral resolution and analysis of the electronic band origin of the transition has provided rotational constants which ar...
Abstract: The and transitions of the CO2+ ion were photographed in emission under high spectral resolution. Analysis of the electronic band origin of the transition has provided rotational constants which ar...
TL;DR: In this paper, the authors used the fact that glyoxal exists in the trans conformer and the pseudo stable cis conformer to calculate a potential function which fits the infrared data of the trans confor...
Abstract: We have shown, using the fact that glyoxal exists in the trans conformer and the pseudo stable cis conformer, a potential function can be calculated which fits the infrared data of the trans confor...
TL;DR: The resonance fluorescence spectrum of Cl2 was photographed at high resolution and analyzed in this article, where the assignments of the lines have been revised and the assignment of the line assignments have been analyzed.
Abstract: The resonance fluorescence spectrum of Cl2 first observed by Rao and Venkateswarlu in 1962, has been photographed at high resolution and analyzed. The assignments of the lines have been revised and...
TL;DR: In this article, the Raman spectra have been obtained from both the e and γ polytypes of GaSe and the frequencies of the phonons at the zone center were obtained for both compounds at 80 and 295 K.
Abstract: Raman spectra have been obtained from both the e and γ polytypes of GaSe. The frequencies of the phonons at the zone center have been obtained for both compounds at 80 K and at 295 K. All modes hav...
TL;DR: The structure of the paraelectric phase of RbHSO4 has been determined by X-ray and neutron diffraction at T −23 °C as discussed by the authors, and the structure consists of two crystallographically independent molecules in the asymmetric unit.
Abstract: The structure of the paraelectric phase of RbHSO4 has been determined by X-ray and neutron diffraction at T = 23 °C. The structure consists of two crystallographically independent molecules in the asymmetric unit. Each of the independent sulphate tetrahedra is linked to a translationally equivalent sulphate by acentrically ordered hydrogen bonds. Some evidence is found for the disordering of one of the sulphate groups in the asymmetric unit. The bond lengths and angles are similar to those found in isomorphous NH4HSO4.
TL;DR: The infrared and Raman spectra of 1,2-dichloroethane and its deuterium compound in the gaseous, liquid, and solid states have been remeasured in the wide range of wavelength by the experimental tec...
Abstract: The infrared and Raman spectra of 1,2-dichloroethane and its deuterium compound in the gaseous, liquid, and solid states have been remeasured in the wide range of wavelength by the experimental tec...
TL;DR: For small internuclear distances, the quadrupole moment of the hydrogen molecule is quadratic in the internuclear distance, with a coefficient determined by the quadrapole shielding factor of the h... as discussed by the authors.
Abstract: For small internuclear distances, the quadrupole moment of the hydrogen molecule is quadratic in the internuclear distance, with a coefficient determined by the quadrupole shielding factor of the h...
TL;DR: Theoretical oscillator strengths for the transitions 3s np1,3P → 3s md 1,3D of Mg are reported in this paper for n = 3,4, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23
Abstract: Theoretical oscillator strengths for the transitions 3s np1,3P → 3s md1,3D of Mg are reported for n = 3,4, … and m = 3,4,…The results are based on an MCHF approximation to the total wave function which includes the correlation of the outer two electrons.
TL;DR: In this paper, the A2Σ+X2Π emission spectrum of HF+, between 3580 and 4830 A, has been photographed at high resolution and measurements on eight bands are reported.
Abstract: The A2Σ+–X2Π emission spectrum of HF+, between 3580 and 4830 A, has been photographed at high resolution and measurements on eight bands are reported. The analysis yields rotational and vibrational...
TL;DR: In this paper, the d.c. conductivity of NaI has been measured in the intrinsic and extrinsic temperature regions and the formation energy Es for the Schottky defects and the energy Em+ for the cation vacancy migrati...
Abstract: The d.c. conductivity of NaI has been measured in the intrinsic and extrinsic temperature regions. The formation energy Es for the Schottky defects and the energy Em+ for the cation vacancy migrati...
TL;DR: In this article, it was shown that a system of communication based on the modulation of the spectrum of a light source is feasible, theoretically as well as experimentally, using a white light source.
Abstract: It is shown, theoretically as well as experimentally, that a system of communication based on the modulation of the spectrum of a light source is feasible. A white light source has been used for th...
TL;DR: In this article, it was shown that the 9-8 P(13) line of the 12C16O laser (1884.349 cm−1) has been used to study laser Stark Lamb dip spectra associated with the R(3/2) line in the rotation-vibration fundamental band of NO.
Abstract: The 9–8 P(13) line of the 12C16O laser (1884.349 cm−1) has been used to study laser Stark Lamb dip spectra associated with the R(3/2) line of the rotation–vibration fundamental band of NO. We have observed fully resolved hyperfine structure (line width ≈ 500 kHz) due to both components, Ω = 3/2 and 1/2, of the 2Π ground state. In addition, two level crossing signals have been observed in the v = 1 vibrational state of the 2Π1/2 component. The values we obtain for the electric dipole moment (in Debye) are:It was possible to determine μ′ and μ″ separately for the 2Π1/2 component because of the observation of the level crossing signals, which depend only on μ′. Our result for μ″ of 2Π1/2 agrees, within error limits, with a more precise previous measurement by molecular beam techniques, and our other results are more precise than previous determinations based on infrared intensities.
TL;DR: In this article, it is proposed to express time as a composition of three auxiliary variables tx, ty, tz which will be named components of vector t Event P is expressed as a combination of six variables x, y, z,
Abstract: It is proposed to express time as a composition of three auxiliary variables tx, ty, tz which will be named components of vector t Event P is expressed as a composition of six variables x, y, z,
TL;DR: In this paper, the distortion moment pure rotational spectrum of 12CH4 in its ground vibronic state was obtained using a conventional Stark modulated microwave spectrometer specially modified for the detection of very weak lines.
Abstract: Seven Q branch transitions between 7.8 and 20 GHz have been observed in the distortion moment pure rotational spectrum of 12CH4 in its ground vibronic state. The spectrum was obtained using a conventional Stark modulated microwave spectrometer specially modified for the detection of very weak lines. From the frequencies of these seven transitions, along with the ortho–para splitting known for the (J = 2) state and two Q branch splittings measured earlier by infrared–microwave double resonance, we have determined the one quartic tensor distortion constant DT, the two sextic constants H4T and H6T, and the three octic constants L4T, L6T, and L8T. These are (in Hz): DT = (132 943.41 ± 0.71); H4T = −(16.9839 ± 0.0076); H6T = (11.0342 ± 0.0086); L4T = (20.27 ± 0.24) × 10−4; L6T = −(26.77 ± 0.35) × 10−4; L8T = −(30.0 ± 1.8) × 10−4. The errors are the standard deviations resulting from a least squares analysis. Estimates are also given of the absolute errors. These results consitute the first measurement of the o...
TL;DR: The Born-Oppenheimer potential energy curve for the B1Σu+ state of the hydrogen molecule has been computed using a wave function in the form of an 88 term expansion in elliptic coordinates and including the interelectronic distance as discussed by the authors.
Abstract: The Born–Oppenheimer potential energy curve for the B1Σu+ state of the hydrogen molecule has been computed using a wave-function in the form of an 88 term expansion in elliptic coordinates and including the interelectronic distance. At R = Re the computed energy is 5.2 cm−1 lower than the previous most accurate value, in agreement with the prediction by Dabrowski and Herzberg. The new potential energy curve, with the previously computed adiabatic corrections, has been used to calculate the vibrational levels for H2, HD, and D2. The resulting dissociation energies differ from the experimental values by less than 1 cm−1. The discrepancies between the theoretical and experimental energies for various vibrational levels amount up to 12 cm−1 for H2 and 8 cm−1 for D2. Their analysis suggests that most of the discrepancy is due to the nonadiabatic effects, but partly also to incomplete convergence of the Born–Oppenheimer potential energy curve, especially at large internuclear separations.
TL;DR: An extensive study of the β system of the PO molecule has been carried out in this article, where the rotational analysis of 23 bands has yielded the constants of the ν ǫ −0 −9 levels of the B2Σ+ state and of the −0 -11 levels.
Abstract: An extensive study of the β system of the PO molecule has been carried out. The rotational analysis of 23 bands has yielded the constants of the ν = 0–9 levels of the B2Σ+ state and of the ν = 0–11...
TL;DR: In this paper, an auroral model which has been found useful in the discussion of auroral spectra and excitation processes is described in detail and the model is similar to that of Rees and Jones and takes into acco...
Abstract: An auroral model which has been found useful in the discussion of auroral spectra and excitation processes is described in detail. The model is similar to that of Rees and Jones and takes into acco...
TL;DR: In this article, CS2+(B2Σu+, A2Πu+ A2 Πu→X 2 Πg) fluorescence bands produced by irradiation of CS2 vapor with emission lines from λλ462-977 A were analyzed and their production cross sections measured.
Abstract: CS2+(B2Σu+, A2Πu → X2Πg) fluorescence bands produced by irradiation of CS2 vapor with emission lines from λλ462–977 A were analyzed and their production cross sections measured. The assignments for...