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Chem5410 Q1 2/20 & 2/27/’06. 1. What is so-called a single-crystal?. 2. What is so-called a powder sample?. 3. Does a powder sample contain single crystals?. 4. What’s the difference between single-crystal diffraction and powder diffraction?.
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Chem5410 Q1 2/20 & 2/27/’06 1. What is so-called a single-crystal? 2. What is so-called a powder sample? 3. Does a powder sample contain single crystals? 4. What’s the difference between single-crystal diffraction and powder diffraction? 5. What is Bragg Law? And what’s the use of it in structure analysis ? 6. In diffraction experiments, what’s the X-ray wavelength used in SXRD? And what’s the X-ray wavelength used in PXRD? 7. What is the suitable size of single crystal for SXRD measurements? 8. How X-rays are generated?
Chem5410 Q2 2/27 & 3/06/’06 1. What are so-called cell constants? How many should be determined? 2. What are so-called the external symmetry of a crystal? 3. What are so-called the internal symmetry of a crystal? 4. What point symmetry groups are possessed by crystals? 5. What is so-called a space group? 6. How to define crystal planes? 7. What’s relationship between lattice planes and cell constants? 8. What’s the so-called the seven crystal
Chem5410 Q3 3/06/’06 1. What are so-called structure Factors? 2. What are so-called lattice types? 3. What are so-called the 14 Bravais lattices? 4. How to determine the cell constants for a crystalline sample? 5. How to determine the correct unit cell for a crystalline sample? 6. How to determine the correct point group for a crystal lattice? 7. What’s the relationship between crystal lattice and diffraction pattern? 8. Why XRD patterns exhibit symmetries?