Showing papers in "Canadian Journal of Physics in 1969"
TL;DR: Ferromagnetic resonance has been observed in single crystals of the family La1−xPbxMnO3 with 0.45 GHz frequency from 13 to 25 GHz and in the temperature range from 77 to 430 °K as discussed by the authors.
Abstract: Ferromagnetic resonance has been observed in single crystals of the family La1−xPbxMnO3with 0.25 < x < 0.45 from 13 to 25 GHz and in the temperature range from 77 to 430 °K. The line width, ΔH, exh...
147 citations
TL;DR: In this paper, the influence of the homogeneous conducting half-space can be represented in terms of an image source located at a complex depth, and it is shown that the influence can be approximated by a single image source.
Abstract: It is shown that the influence of the homogeneous conducting half-space can be represented approximately in terms of an image source located at a complex depth.
144 citations
TL;DR: The ungerade singlet states of molecular nitrogen observed up to 115,000 cm−1 have traditionally been designated with some 20 letter symbols as discussed by the authors, but these levels do not belong to 20 different electronic states but that all of them can be ordered into six vibrational progressions of three valence states: b1Πu (j, b, d, m, p, q), b′ 1Σu+ (b′, g, g′, f, r, r), d′(1Ω− or 1Δu?),
Abstract: The ungerade singlet states of molecular nitrogen observed up to 115 000 cm−1 have traditionally been designated with some 20 letter symbols. It is shown that these levels do not belong to 20 different electronic states but that all of them can be ordered into six vibrational progressions of three valence states: b1Πu (j, b, d, m, p, q), b′ 1Σu+ (b′, g, g′, f, r), d′(1Σu− or 1Δu?), and of three Rydberg states: c1Πu (l, d″), c′ 1Σu+ (p′, r′, k, s′, h, h′), and o1Πu. The new assignments of observed levels to the states b, b′, c, and c′ are identical with those given by Carroll and Collins on the basis of new high-resolution studies of the absorption spectrum. It is shown here, that the irregularities of the vibrational intervals, rotational constants, isotope shifts, and intensity distributions within these progressions can be interpreted quantitatively on the basis of homogeneous interactions between valence and Rydberg states of the same species, especially between the pairs of states b1Πu + c1Πu and b′ 1...
128 citations
TL;DR: In this article, the 0-0 bands at 1474 A and 1422 A of the first two members of the nf-X2Π Rydberg series of NO have been observed under high resolution in the absorption spectrum of cold nitric oxide gas.
Abstract: The 0–0 bands at 1474 A and 1422 A of the first two members of the nf–X2Π Rydberg series of NO have been observed under high resolution in the absorption spectrum of cold nitric oxide gas. They sho...
127 citations
TL;DR: In this article, high-resolution studies of the absorption spectrum of N2 have been made in the region 1015-795 A. Analyses were given of 25 non-Rydberg bands of the type 1Πu-X1Σg+
Abstract: New high resolution studies of the absorption spectrum of N2 have been made in the region 1015–795 A. Analyses are given of 25 non-Rydberg bands of the type 1Πu–X1Σg+. It is shown that all of these...
115 citations
TL;DR: In this paper, the B2Σ++→A2 ε+ε+ and A2ε + ε−ε−1 systems of OD and OH were photographed at high resolution and the apparent dissociation energy was calculated to be (18.847 cm−1 for OD and (19.263 cm −1 for OH).
Abstract: The B2Σ+ → A2Σ+ and C2Σ+ → A2Σ+ systems of OH and OD were photographed at high resolution. The apparent dissociation energy D0(A2Σ+) is calculated to be (18 847 ± 15) cm−1 for OH and (19 263 ± 15) ...
94 citations
TL;DR: The vibrational structures of the 1744-A Rydberg transitions of C2H4 and C2D4 have been examined in detail in this paper, and the relative intensities of the principal bands have been measured for both isotopes.
Abstract: The vibrational structures of the 1744 A Rydberg transitions of C2H4 and C2D4 have been examined in detail. For both isotopes the relative intensities of the principal bands have been measured, and...
83 citations
TL;DR: In this article, the lattice dynamics of III-V compounds has been investigated on a "rigid ion" type of model and the interactions are assumed to consist of Coulomb forces with an effective charge and a general force.
Abstract: The lattice dynamics of III–V compounds has been investigated on a 'rigid ion' type of model. The interactions are assumed to consist of Coulomb forces with an effective charge and a general force ...
83 citations
TL;DR: In this paper, the absorption spectrum of SO radicals produced by flash photolysis of a mixture of COS + O2 + Ar was investigated, and a partial rotational analysis of the previously known bands of the B3Σ−−−X3 Σ− trans...
Abstract: The absorption spectrum of SO radicals produced by flash photolysis of a mixture of COS + O2 + Ar is investigated. A partial rotational analysis of the previously known bands of the B3Σ−–X3Σ− trans...
81 citations
TL;DR: The ultraviolet absorption spectrum of HCP has been observed from 4100 to about 2350 A, and seven electronic transitions have been identified as mentioned in this paper, three of these transitions involve excited singlet s...
Abstract: The ultraviolet absorption spectrum of HCP has been observed from 4100 A to about 2350 A, and seven electronic transitions have been identified. Three of these transitions involve excited singlet s...
75 citations
TL;DR: In this paper, the vibrational functions associated with two (or three) crossing Morse curves are used to set up an interaction matrix and the eigenvalues of this matrix are compared with the observed levels and the "deperturbed" Morse curve are obtained by a least-squares fitting.
Abstract: A method to obtain a "deperturbation" of perturbed vibrational levels is developed The vibrational functions associated with two (or three) crossing Morse curves are used to set up an interaction matrix The eigenvalues of this matrix are compared with the observed levels and the "deperturbed" Morse curves are obtained by a least-squares fitting This method applied to the 1Σu+ states of N2 confirms the interpretation given by Dressler (following paper)
TL;DR: In this paper, the transfer of electronic energy in collisions between an excited alkali atom MA*(2Pj) and an unexcited atom MB(2S1/2) was considered.
Abstract: Possible mechanisms are considered for the transfer of electronic excitation energy in collisions between an excited alkali atom MA*(2Pj) and an unexcited atom MB(2S1/2). It is shown that a dipole–...
TL;DR: In this article, three limiting curves of predissociation for the F1, F2, and F3 components of the state B3Zu− of S2 have been obtained following a detailed rotational analysis of emission and absorption bands.
Abstract: Three limiting curves of predissociation for the F1, F2, and F3 components of the state B3Zu− of S2 have been obtained following a detailed rotational analysis of emission and absorption bands of 32S2, 34S2, and 32S34S. The three curves extrapolate to identical limits, at 35 999.0 ± 2.5 cm−1 above the minimum in X3Σg−. The predissociating state is thereby identified as a 1u state, and arguments based upon (i) the noncrossing rule for states of like Ω and (ii) a comparison of the observed shapes of the limiting curves with those calculated on the basis of long-range forces, indicate that the products at this limit are S(3P2) + S(3P1). D00 (32S2) is then 35 216.4 ± 2.5 cm−1, or 100.69 ±.01 kcal mole−1.
TL;DR: In this paper, the electrolyte technique has been used to measure the electrical reflectance of alloys of the InAsxSb1−x, InAs 1−xPx, and GaxIn 1−Sb systems and the variation of the values of E1, E1+Δ 1, E0′, and E1
Abstract: Electroreflectance measurements by the electrolyte technique have been made on alloys of the InAsxSb1−x, InAs1−xPx, and GaxIn1−xSb systems and the variation of the values of E1, E1 + Δ1, E0′, and E...
TL;DR: In this paper, the intensity profiles of some of the broad continuous absorption bands of oxygen in the near-infrared and visible regions were measured in the compressed gas over a range of pressures and temperat...
Abstract: The intensity profiles of some of the broad continuous absorption bands of oxygen in the near-infrared and visible regions were measured in the compressed gas over a range of pressures and temperat...
TL;DR: In this paper, the proton and deuteron spin-lattice relaxation time T1 was measured in CH4, CD4, CHD3, CH3D, and CH4-CD4 mixtures as a function of temperature between 1.2 °K and 60 °...
Abstract: The proton and deuteron spin–lattice relaxation time T1 has been measured in CH4, CD4, CHD3, CH3D, and CH4–CD4 mixtures and CH4–krypton mixtures as a function of temperature between 1.2 °K and 60 °...
TL;DR: Using inelastic scattering of slow neutrons, the frequency-wavevector dispersion relations for the lattice vibrations in the face-centered cubic alloys Ni3Fe, Ni0.5Fe 0.7, and Cu3Zn have been derived as discussed by the authors.
Abstract: Using inelastic scattering of slow neutrons, the frequency-wavevector dispersion relations for the lattice vibrations in the face-centered cubic alloys Ni3Fe, Ni0.5Fe0.5, Ni0.3Fe0.7, and Cu3Zn have...
TL;DR: In this article, the last of a set of five papers reporting latitude surveys carried out in 1965 and 1966 at the time of and soon after the IQSY cosmic-ray maximum, the observations are reduced to a common...
Abstract: In this, the last of a set of five papers reporting latitude surveys carried out in 1965 and 1966 at the time of and soon after the IQSY cosmic-ray maximum, the observations are reduced to a common...
TL;DR: The static magnetization of the family of compounds La1−xPbxMnO3(0.25) has been measured from close to absolute zero to about 800 °K.
Abstract: The static magnetization of the family of compounds La1−xPbxMnO3(0.25 < x < 0.45) has been measured from close to absolute zero to about 800 °K. The compounds are ferromagnetic, with Curie temperat...
TL;DR: In this paper, the authors investigated the direct collection of Fe, Co, Ni, Cu, Zn, and Sn ions in the energy range from about 10 eV to 110 eV in an electromagnetic isotope separator.
Abstract: The direct collection of Fe, Co, Ni, Cu, Zn, and Sn ions has been investigated in the energy range from about 10 eV to 110 keV in an electromagnetic isotope separator. At low energies the ions build up a layer on the surface of the graphite block used as a backing, while at high energies only a certain saturation value can be collected. For these ions the highest energies at which the building-up of a layer was observed were 1.5 keV, 1.0 keV, 0.8 keV, 0.3 keV, 0.3 keV, and 0.45 keV, respectively. In the building-up region the efficiency of the collection process and the sticking probability of ions as a function of energy have been measured. From these the self-sputtering ratios have been calculated. In the saturation region the amounts of material collected have been measured and the ranges of ions in graphite backings saturated with metal atoms have been calculated theoretically. This calculation gives an estimate of the metal atom concentrations in the graphite, which in turn determines the sputtering ...
TL;DR: In this paper, the Lamb dip technique is used at microwave frequencies to identify the centers of absorption lines very precisely, and the possibility of using this technique to stabilize oscillators is discussed.
Abstract: An experiment is described which shows that the saturation dip technique (often termed the Lamb dip, in the laser field) can be used at microwave frequencies to identify the centers of absorption lines very precisely. The use of this technique in microwave spectroscopy is illustrated and the possibility of using this technique to stabilize oscillators is discussed.
TL;DR: In this article, single crystals of La1−xPbxMnO3 with 0.25 Ã 0.45 Ã 1−xpbxmnsO3 were grown by the flux technique and X-ray fluorescence, wet chemical and electron microprobe analyses indicate the crystals are homogeneous.
Abstract: Single crystals of La1−xPbxMnO3 with 0.25 < x < 0.45 have been grown by the flux technique. X-ray fluorescence, wet chemical, and electron microprobe analyses indicate the crystals are homogeneous ...
TL;DR: In this article, the stabilization of fingers in a specific oil-water displacement process with capillary pressure has been statistically discussed for a given heterogeneous porous medium and the equation of motion has been analyzed.
Abstract: The stabilization of fingers in a specific oil–water displacement process with capillary pressure has been statistically discussed for a given heterogeneous porous medium. The equation of motion ha...
TL;DR: In this article, different relations between the nuclear level density parameter a and the mass shell correction S were obtained for different types of mass shell corrections, and the relationship between the two parameters was shown to be linear.
Abstract: Previous work by Gilbert and Cameron has demonstrated a linear relation between the nuclear level density parameter a and the mass shell correction S. However, different relations were obtained for...
TL;DR: In this article, the existence of the potassium resonance line was verified by using an absorption cell and several problems of measuring the emissions and of subsequently calculating a density distribution were discussed, and the results of the measurements showed that the seasonal variations of sodium and lithium twilight abundances are similar with additional sharp enhancements of lithium abundances thought to be due to natural and manmade injections of lithium.
Abstract: Twilight resonance emissions due to atmospheric sodium, lithium, and potassium have been measured for over one year. The existence of the potassium resonance line was verified by using an absorption cell.Several problems of measuring the emissions and of subsequently calculating a density distribution are discussed. The widths of about 13 km and the topside scale heights of about 4.5 km obtained for the sodium layer are significantly less than obtained at Saskatoon in previous measurements. Atmospheric transmission functions have been recalculated with the results that the sodium and lithium layers are both at about the same height of around 90 km. A lower height of about 85 km was obtained for the potassium layer.The seasonal variations of sodium and lithium twilight abundances are shown to be similar with additional sharp enhancements of lithium abundances thought to be due to natural and man-made injections of lithium. Any seasonal variations of the potassium abundances in the lower layer were masked b...
TL;DR: In this article, the effects of resonance radiation in potassium vapor and of collisions between excited potassium atoms and N2, H2, HD, and D2 molecules, on the measured lifetimes of the 42P states, have been investigated by the method of delayed coincidences.
Abstract: The effects of imprisonment of resonance radiation in potassium vapor and of collisions between excited potassium atoms and N2, H2, HD, and D2 molecules, on the measured lifetimes of the 42P states, have been investigated by the method of delayed coincidences. The potassium atoms were excited with short pulses of resonance radiation, and the delays between the exciting and fluorescent pulses were measured with a time-to-amplitude converter. At pure potassium densities below 1010 atoms/cm3, the measured lifetimes approach the constant values 27.8 ± 0.8 and 27.6 ± 0.8 ns, corresponding to the natural lifetimes of the 42P1/2 and 42P3/2 states, respectively. At higher densities the effective lifetimes are in satisfactory agreement with the predictions of Holstein's theory. The decrease in the measured decay rates observed upon addition of the diatomic gases yielded cross sections for quenching collisions with N2, H2, HD, and D2 which equal 34.0 ± 2.0 A2, 9.4 ± 1.3 A2, 11.9 ± 1.5 A2, and 8.0 ± 2.0 A2, respecti...
TL;DR: In this article, three new electronic transitions of the C2 molecule have been observed in absorption in the region 1300-1450 A. The system of shortest wavelength is readily identified as a 1Πu−1Σg+ transition; the...
Abstract: Three new electronic transitions of the C2 molecule have been observed in absorption in the region 1300–1450 A. The system of shortest wavelength is readily identified as a 1Πu–1Σg+ transition; the...
TL;DR: In this paper, a Zener double exchange model is formulated for magnetite and is used to describe the electron-hopping process, and the main consequence of this model is that the electrons participating in the hopping process in any imperfect or nonstoichiometric (i.e. real) sample of magnetite can be regarded as being essentially localized to hopping within particular (Fe2+−Fe3+) octahedral cation pairs, and not as being in either some form of 3D conduction band or as participating in a nonlocalized electron-transfer process.
Abstract: A Zener double-exchange model is formulated for magnetite and is used to describe the electron-hopping process. The main consequence of this model is that the electrons participating in the hopping process in any imperfect or nonstoichiometric (i.e. real) sample of magnetite can be regarded as being essentially localized to hopping within particular (Fe2+–Fe3+) octahedral cation pairs, and not as being in either some form of 3d conduction band or as participating in a nonlocalized electron-transfer process. Well-known results on the electrical conductivity, and new results with the Mossbauer effect in magnetite are then explained in terms of this pair-localized electron-hopping model.
TL;DR: The absorption spectrum of bromine has been photographed in the first and higher orders of a 10.7m. concave vacuum grating spectrograph in the region 1700-1170 A as discussed by the authors.
Abstract: The absorption spectrum of bromine has been photographed in the first and higher orders of a 10.7-m. concave vacuum grating spectrograph in the region 1700–1170 A.A number of band systems have been...
TL;DR: In this paper, the effects of quantum deviations from classical behavior of simple fluids are examined using the recently developed perturbation theory of fluids using the 6:12 potential, and the theory is applied to gaseous helium and hydrogen with good results.
Abstract: The effects of quantum deviations from classical behavior of simple fluids are examined using the recently developed perturbation theory of fluids. The free energy is expanded in powers of Planck's constant and in powers of the strength of the attractive potential about an unperturbed system of hard spheres whose diameter is chosen to take into account the softness of the repulsive potential. Using the 6:12 potential, the theory is applied to gaseous helium and hydrogen with good results, and to liquid neon with satisfactory results.