Skip to content

Crystallography Made Crystal Clear

Metadata

  • Author: Gale Rhodes
  • ASIN: B006FG1I1S
  • ISBN: 978-0125870733
  • Reference: https://www.amazon.com/dp/B006FG1I1S
  • Kindle link

Highlights

all other regularly spaced planes that can be drawn through lattice points can be thought of as sources of diffraction — location: 1181 ^ref-26882

each face of an orthorhombic unit cell is labeled with the indices of the set of planes that includes that face. (The crossed arrows lie on the labeled face, and parallel faces have the same indices.) — location: 1191 ^ref-58277

(To recognize these planes easily, notice that if you think of the index as (abc), the zeros tell you the location of the plane: the zeros in (010) occupy the a and c positions, so the plane corresponds to the ac face.) — location: 1198 ^ref-1001

an entire set of parallel planes, not just one plane, acts as a single diffractor and produces one reflection.) — location: 1201 ^ref-38738

that the planes cut each a edge of each unit cell into two parts and each b edge into one part, so these planes have indices 210. — location: 1206 ^ref-62997

each set of parallel planes — location: 1236 ^ref-10252

sets) is treated as an independent diffractor and produces a single reflection. — location: 1237 ^ref-15955

each atom or each small volume element of electron density is treated as an independent diffractor, represented by one term in a Fourier sum that describes each reflection. — location: 1238 ^ref-2227

only if θ meets the condition — location: 1247 ^ref-45032

(two angles are equal if corresponding sides are perpendicular). — location: 1259 ^ref-56260

way: If X-rays impinge at an angle θ’ that does not satisfy the Bragg conditions, then for every reflecting plane p, there will exist, at some depth in the crystal, another parallel plane p’ producing a wave precisely 180° out of phase with that from p, and thus precisely cancelling the wave from p. — location: 1266 ^ref-1734

intensity of this diffracted ray will depend on how many atoms, or much electron density, lies on this set of planes in the unit cell. — location: 1273 ^ref-63222

the angle of diffraction θ is inversely related to the interplanar spacing dhkl — location: 1276 ^ref-12468

(sin θ is proportional to 1/dhkl). — location: 1277 ^ref-46054

each set of parallel planes in the crystal produces one reflection, — location: 1285 ^ref-40178

one term in the Fourier sum that describes the electron density within the unit cell. — location: 1286 ^ref-39846

the points in this reciprocal lattice — location: 1291 ^ref-62757

are guides that tell the crystallographer the angles at which all reflections will occur. — location: 1292 ^ref-27743

the largest aggregate of molecules that possesses no symmetry elements, but can be juxtaposed on other identical entities by symmetry operations, is called the asymmetric unit. — location: 1491 ^ref-64386

Because of protein chirality, symmetry elements in protein crystals include only translations, rotations, and screw axes, — location: 1498 ^ref-21276

screw axis — location: 1507 ^ref-64764

because the operation of a 21 screw axis interchanges these positions. — location: 1526 ^ref-52703