Showing papers in "Acta Crystallographica in 1955"
TL;DR: In this paper, Hartman and Perdok made an attempt to find relations between crystal structure and crystal morphology on an energy basis, and concluded that the morphology of a crystal is governed by chains of strong bonds running through the structure.
Abstract: An attempt is made by Hartman & Perdok to find relations between crystal structure and crystal morphology on an energy basis. It is concluded that the morphology of a crystal is governed by chains of strong bonds running through the structure.
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TL;DR: BOKHOVEN, C., SCHOONE, J. C. as mentioned in this paper, and WOOLFSON, M. M. (1955). Acta Gryst.
Abstract: BOKHOVEN, C., SCHOONE, J . C. ~; BIJVOET, J . i~. (1951). Acta Cryst. 4, 275. COCHRA~, W. & WOOLFSON, M. M. (1955). Acta Gryst. 8 ,1 . ~AUPT~A_~, H. & ~ , J. (1953). Solution of the Phase Problem. I. The Centrosymmetric Crystal. A.C.A. Monograph No. 3. Wilmiugton: The Letter Shop. SAYP.E, D. (1952). Acta Gryst. 5, 60. WATSOn, G. N. (1922). A Treatise on the Theory of Bessel 2'unctions. Cambridge: University Press. WrLSO~¢, A. J . C. (1949). Acta Cryst. 2, 318. WOOLFSON, M. M. (1954). Acta Cryst. 7, 61.
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TL;DR: In this article, the real and imaginary dispersion corrections for the x-ray scattering factors for elements 20 to 96 for K radiation of chromium, copper, and molybdenum were tabulated.
Abstract: Values are tabulated for the real and imaginary dispersion corrections for the x-ray scattering factors for elements 20 to 96 for K radiation of chromium, copper, and molybdenum. 0:
145 citations
TL;DR: A new analysis of the scattering data for the protein particle associated with turnip yellow mosaic virus (Sehmidt et al., 1954) has been made using the methods outlined above as discussed by the authors.
Abstract: A new analysis of the scattering data for the protein particle associated with turnip yellow mosaic virus (Sehmidt et al., 1954) has been made using the methods outlined above. At the time the data were published, hollow-sphere functions corrected for slits of infinite height and negligible width had not been calculated, and so the data were interpreted by extrapolation from available calculations, giving a sphere radius of 140/~, and an h of 0.75. Applying the same correction for the effects of the finite slit widths as was used by Schmidt et al. for turnip yellow mosaic nucleoprotein, use of Tables 1 and 2 and the methods described above essentially confirms the previous results.
TL;DR: In this paper, the crystallographic constants of two forms of phenazine and four forms of acridine were measured and the structure problem was solved by the method of the molecular Fourier transform.
Abstract: In a survey of heterocyclic compounds suited to both experimental and theoretical study of molecular dimensions, the crystallographic constants of two forms of phenazine and of four forms of acridine were measured. ~-Phenazine was chosen as the most suitable crystal structure for a detailed X-ray analysis. The intensities of 714 reflections (including 682 out of a possible total of 1024 within the limiting sphere for Cu Ks) were estimated visually. The structure problem was solved by the method of the molecular Fourier transform. Refinement was achieved in the hOl zone by Fourier methods and in the h/c0 and 0]d zones by the method of least squares. The coordinates from the two-dimensional analysis were refined by one least-squares treatment of the F(hkl) to a new set of coordinates, which corresponded to R(hkl) = O. 16. Final parameters were computed by one set'of Fo and Fc differential syntheses. The electron-density distribution in the best plane through the atomic centres was calculated by a direct Fourier method. The standard deviation a(x) of the final atomic coordinates was estimated to be 0.009 A; within the limits of error the molecule has symmetry mmm. The crystal and molecular structures of phenazine are discussed in Part II.