What's the difference between orthorhombic and rhombohedral?

Orthorhombic


Definition:

  • (a.) Noting the system of crystallization which has three unequal axes at right angles to each other; trimetric. See Crystallization.

Example Sentences:

  • (1) Based on the refined atomic coordinates of the tRNAphe in the orthorhombic crystal, on the recent advances in the distance dependence of the ring-current magnetic field effects and on the adopted values for the isolated hydrogen-bonded NH resonances, a computed spectrum consisting of 23 protons was constructed.
  • (2) 261, 16207-16209) that recombinant murine interferon-beta produced in Escherichia coli was crystallized in an orthorhombic space group C222(1) using polyethyleneglycol 8000 as precipitant, the crystals had an insufficient resolution and a marked tendency for orientational disorder around the c axis.
  • (3) The mutant proteins were screened for their ability to crystallize into the orthorhombic form and bind mercury ions isomorphously.
  • (4) In the orthorhombic crystal lattice, tRNA(Asp) molecules are associated by anticodon-anticodon interactions through a two-fold symmetry axis.
  • (5) The melamine forms disordered crystals of orthorhombic symmetry with a = 11.957(3), b = 17.267(3), c = 5.769(3)A.
  • (6) The crystals have a rhombic prismatic habit and belong to the orthorhombic space group C222(1) with unit cell dimensions a = 130 A, b = 213 A and c = 216 A. X-ray structure determination is underway.
  • (7) The subcell (HS1) is orthorhombic with as = 10.3, bs = 7.5 and cs = 2.54 A.
  • (8) N-Z-L-Pro-D-Ala-OMe, C17H22N2O5, Mr = 334.38, crystallizes in the orthorhombic space group P2(1)2(1)2(1), with the cell dimensions a = 5.005 (5), b = 17.690 (9) and c = 18.70 (1) A3, V = 1656.3 A3, Z = 4, Dx = 1.341 g cm-3, Cu K alpha, lambda = 1.54184 A, mu = 7.830 cm-1, F(000) = 712, T = 198 K, final R (on F) = 0.036 for 1575 observed reflections with I greater than or equal to 3 sigma(I).
  • (9) The crystals are orthorhombic, space group P212121, with a=8.611(2), B=6.138(2), And c=14.912(4) A. Least-squares refinements yielded a conventional R-factor of 0.036.
  • (10) The atomic coordinates of yeast phenylalanine transfer RNA (tRNA) as well as the torsion angles of the polynucleotide chain are presented as derived from an x-ray diffraction analysis of orthorhombic crystals.
  • (11) These crystals diffract to 3.4 A and the observed diffraction is consistent with orthorhombic space groups P4(1) and P4(3).
  • (12) Yeast phenylalanyl transfer RNA crystallizes in a simple orthorhombic unit cell (a = 33.2, b = 56.1, c = 161 A), and the crystal yields an x-ray diffraction pattern with a resolution of 2.3 A.
  • (13) Concanavalin A, a phytohemagglutinin isolated from the jack bean, crystallizes at pH 6.8 in the orthorhombic space group 1222 with a = 89.9, b = 87.2, and c = 63.1 A.
  • (14) C20H24O4, Mr = 328.41, orthorhombic, P2(1)2(1)2(1), a = 11.688 (3), b = 15.377 (5), c = 9.466 (2) A, V = 1701 (1) A3, Z = 4, Dx = 1.282 g cm-3, lambda (Mo K alpha) = 0.71073 A, mu = 0.823 cm-1, F(000) = 704, T = 298 K, R = 0.063 for 1921 reflections with F greater than 2 sigma (F).
  • (15) Above this temperature, this "orthorhombic" phase converts directly to the liquid-crystalline phase.
  • (16) The crystals exhibit strong F222 pseudo symmetry but belong to the orthorhombic space group C222 or C222(1), with cell parameters a = 73.8 A, b = 119.9 A and c = 133.2 A with two molecules per asymmetric unit.
  • (17) The crystal form is of the orthorhombic space group P2(1)2(1)2, with unit cell dimensions a = 150 A and b = 129 A.
  • (18) Crystals of methyl 3-O-beta-D-glucopyranosyl-beta-D-glucopyranoside (methyl beta-D-laminarabioside) belong to the orthorhombic system, space group P2(1)2(1)2, with a = 14.548(2), b = 24.252(7), c = 4.938(1) A, and Z = 4.
  • (19) The receptor fragment crystallizes in the orthorhombic space group P2(1)2(1)2(1), a = 105.5 A, b = 224.5 A, c = 363.5 A.
  • (20) 1-(2,6-Dihydroxy-4-methoxyphenyl)-3-(4-methoxyphenyl)-2-propen-1-o ne, C17H16O5, Mr = 300.31, orthorhombic, Pbca, a = 27.903 (3), b = 13.958 (2), c = 7.662 (1) A, V = 2984 (1) A3, Z = 8, D chi = 1.337 Mg m-3, lambda(Cu K alpha) = 1.5418 A, mu = 0.729 mm-1, F(000) = 1264, T = 295 K, R = 0.040 for 1702 observed reflections.

Rhombohedral


Definition:

  • (a.) Related to the rhombohedron; presenting the form of a rhombohedron, or a form derivable from a rhombohedron; relating to a system of forms including the rhombohedron and scalenohedron.

Example Sentences:

  • (1) Crystal structure analysis and refinement at 2.0 A resolution of a rhombohedral crystal form of human annexin V at high calcium concentration revealed a domain motion compared to the previously analysed hexagonal crystal form.
  • (2) Hexagonal rods were compared to rectangular or rhombohedral rods.
  • (3) Assuming the organic template covers the crystal exterior, the projected rhombohedral segment, appearing hexagonal, would seem to contain the protein, hence explaining the apparent presence of the crystal ghost.
  • (4) Furthermore, under conditions known to lead to the formation of rhombohedral crystals of canavalin, a limiting size is reached at high concentrations of canavalin.
  • (5) The inspection of these surfaces using SEM and EDX revealed hexahedrally based crystals including pseudocuboidal, rhombohedral and variable rugged rocky shapes.
  • (6) Detailed analysis of the structure of a single bilaminar lamella shows that each sheet of the two-sheet structure is identical and made up of repeating rhombohedral units whose principal axes are in the ratio of 2:1.
  • (7) The crystals were rhombohedral with an edge length of 0.4 mm.
  • (8) Whereas segments of hexagonal rods in the section should project as octagons at the electron microscope imaging plane, and octagonal profiles are never found, rectangular or rhombohedral rod segments project as hexagons.
  • (9) Precession photographs show that they belong to the rhombohedral space group R3 with unit cell dimensions a = b = 145.4 A, c = 47.5 A, alpha = beta = 90 degrees and gamma = 120 degrees.
  • (10) In naturally desensitized areas on the same dentin surface, most of the dentinal tubules were obturated with rhombohedral crystals of all sizes; membranous structures were not observed in these tubules.
  • (11) The paper describes the arrangement of the atoms within rhombohedral crystals of 2Zn pig insulin as seen in electron density maps calculated from X-ray data extending to 1.5 A (1 A = 10(-10) m = 10(-1) nm) at room temperature and refined to R = 0.153.
  • (12) Rhombohedral crystals grow in 1.8 to 2.0 M ammonium sulfite, pH 7.8 at 21 degrees C, and tetragonal crystals grow in 2.6 M magnesium sulfate, pH 5.5 at 25 degrees C. Analysis of TNF by isoelectric focusing under native and denaturing conditions indicates that TNF molecules exist as trimers in solution.
  • (13) In the presence of 1% phenol, 1.0 M sodium chloride, and at a pH of 8.5, a rhombohedral form is produced with two monomers in the asymmetric unit, space group R3, a = 79.92 A and c = 40.39 A.
  • (14) Mg-containing calcium phosphate crystals including pseudocuboidal, rhombohedral shapes and groupings of quadrangular blades cubically arranged were found in human tooth enamel by scanning electron microscopy and by electron probe microanalysis.
  • (15) The hydrolytic cleavage of the peptide backbone takes place only in preparations containing rhombohedral crystals in addition to free zinc ions.
  • (16) The size measured corresponds to an aggregate of trimers making a unit rhombohedral cell consistent with x-ray crystallographic data (McPherson, A.
  • (17) C43, 1653-1655] is properly described as rhombohedral, space group R3c, with a = 12.355 (4) A, a = 51.01 (2) degrees, Z = 2.
  • (18) Crystals and rhombohedral aggregates of calcite, aggregates of small crystals and tabular crystals of vaterite and fibrous radial aggregates in the form of ooliths were found.
  • (19) Some otoconia are exceptions, evidently seeding and growing in the pure rhombohedral form.
  • (20) The second crystal form is rhombohedral with dimensions unit cell a = 121.1 A, alpha = 60 degrees, space group R32 and diffracts to a resolution of 3.5 A.