
An introduction to minerals and rocks under the microscope
... Rocks are made of minerals and, as minerals are natural crystals, the geological world is mostly a crystalline world. Many large-scale geological processes, such as the movement of continents and the metamorphism of large volumes of rock during mountain building, represent the culmination of microsc ...
... Rocks are made of minerals and, as minerals are natural crystals, the geological world is mostly a crystalline world. Many large-scale geological processes, such as the movement of continents and the metamorphism of large volumes of rock during mountain building, represent the culmination of microsc ...
Copyright 2010 Scott R
... Na(H3BNMe2BH3), in tetrahydrofuran produces the new complex Th(H3BNMe2BH3)4. The thorium center forms bonds with fifteen hydrogen atoms; accordingly, this is the first example of a fifteen-coordinate atom of any kind. As determined by both single crystal X-ray and single crystal neutron diffraction ...
... Na(H3BNMe2BH3), in tetrahydrofuran produces the new complex Th(H3BNMe2BH3)4. The thorium center forms bonds with fifteen hydrogen atoms; accordingly, this is the first example of a fifteen-coordinate atom of any kind. As determined by both single crystal X-ray and single crystal neutron diffraction ...
electronic reprint Structure of a new crystal form of
... Stereoview of buried hydrophobic residues in the Ub4-2/cl structure. Ubiquitin moieties are colored as in Fig. 2(a). Leu8, Ile44 and Val70 in each ubiquitin moiety are shown in CPK format and colored pink, orange and cyan, respectively. The Ub2 structure, including the buried hydrophobic interface, ...
... Stereoview of buried hydrophobic residues in the Ub4-2/cl structure. Ubiquitin moieties are colored as in Fig. 2(a). Leu8, Ile44 and Val70 in each ubiquitin moiety are shown in CPK format and colored pink, orange and cyan, respectively. The Ub2 structure, including the buried hydrophobic interface, ...
ANNEX (Manuscrits posteriors a la Comissió de Doctorat de Juliol del...
... Asymmetric unit of [PPN][3] consists of half of [8,8’-(CH3)2-3,3’Co(1,2-C2B9H10)2]- or [3]- complex unit, with the metal occupying at inversion center, and half of [PPN]+ ion, with the nitrogen atom at 2-fold axis. Thus the methyl groups of the centrosymmetric [3]moiety as well as the cage carbons l ...
... Asymmetric unit of [PPN][3] consists of half of [8,8’-(CH3)2-3,3’Co(1,2-C2B9H10)2]- or [3]- complex unit, with the metal occupying at inversion center, and half of [PPN]+ ion, with the nitrogen atom at 2-fold axis. Thus the methyl groups of the centrosymmetric [3]moiety as well as the cage carbons l ...
Octahedral and Tetrahedral Cobalt(II) Sites in Cobalt Chloride
... of cobalt(II) and zinc chloride exhibit coordination numbers 4/6 in dinuclear dme complexes (1 and Ref. 14) and coordination number 4 in mononuclear tetramethylethylenediamine (tmeda) complexes.29,30 On the contrary, the MnCl2 complexes exhibit coordination ...
... of cobalt(II) and zinc chloride exhibit coordination numbers 4/6 in dinuclear dme complexes (1 and Ref. 14) and coordination number 4 in mononuclear tetramethylethylenediamine (tmeda) complexes.29,30 On the contrary, the MnCl2 complexes exhibit coordination ...
Are sites with multiple single nucleotide variants in cancer genomes
... 20 base pairs. P < 0.001 for observing >7 sites with 3 SNVs in A),B) and C) if SNVs were randomly ...
... 20 base pairs. P < 0.001 for observing >7 sites with 3 SNVs in A),B) and C) if SNVs were randomly ...
Linear Trichromium Complexes with Direct Cr to
... bonded CrII atoms to which a CrIII atom is attached. No symmetrical chain has been found, contrary to a previous preliminary report. The seven compounds have been well characterized crystallographically, and their short and long Cr to Cr distances (Å, in parentheses) are: 1 [Cr3(dpa)4Cl2]Cl‚2CH2Cl2‚ ...
... bonded CrII atoms to which a CrIII atom is attached. No symmetrical chain has been found, contrary to a previous preliminary report. The seven compounds have been well characterized crystallographically, and their short and long Cr to Cr distances (Å, in parentheses) are: 1 [Cr3(dpa)4Cl2]Cl‚2CH2Cl2‚ ...
Cation distribution and crystal chemistry of Y3Al5
... Five single crystals of Y3Al5ÿxGaxO12 (0 x 5) garnet solid solutions with the compositions x = 0.0, 1.0, 2.0, 3.0 and 4.0 were synthesized using a ¯ux method. The compositional dependence of the lattice constants of the garnet solid solutions shows a large deviation from Vegard's law. Investigat ...
... Five single crystals of Y3Al5ÿxGaxO12 (0 x 5) garnet solid solutions with the compositions x = 0.0, 1.0, 2.0, 3.0 and 4.0 were synthesized using a ¯ux method. The compositional dependence of the lattice constants of the garnet solid solutions shows a large deviation from Vegard's law. Investigat ...
Second Harmonic Generation in Photonic Crystals UNIVERSITAT POLITECNICA DE CATALUNYA
... the fundamental and SH beams necessary for a continuous growth of the SH intensity is provided by the bending of the dispersion curve at the boundary of the forbidden zone or Bragg reflection band. Since each crystal has a different lattice constant, it is expected that the resulting SH beam appears ...
... the fundamental and SH beams necessary for a continuous growth of the SH intensity is provided by the bending of the dispersion curve at the boundary of the forbidden zone or Bragg reflection band. Since each crystal has a different lattice constant, it is expected that the resulting SH beam appears ...
feature articles
... equivalent to the one that would be followed with singlecrystal diffraction data, although includes modifications such as histogram matching with chemical composition (Baerlocher et al., 2007). Recently it has also been reported that the solution obtained with application of the charge-flipping meth ...
... equivalent to the one that would be followed with singlecrystal diffraction data, although includes modifications such as histogram matching with chemical composition (Baerlocher et al., 2007). Recently it has also been reported that the solution obtained with application of the charge-flipping meth ...
Reverse Watson-Crick Base - Vanderbilt Center for Structural Biology
... duplexes with single nucleotides overhanging at the 50 -ends. The overhanging nucleotide from one strand remains stacked and sandwiched between the blunt-ends of two adjacent Z-DNA duplexes, while the overhanging base of the opposing strand is extra-helical. The stacked and the extra-helical bases f ...
... duplexes with single nucleotides overhanging at the 50 -ends. The overhanging nucleotide from one strand remains stacked and sandwiched between the blunt-ends of two adjacent Z-DNA duplexes, while the overhanging base of the opposing strand is extra-helical. The stacked and the extra-helical bases f ...
Atomic-resolution Crystal Structures of B
... Heinemann & Hahn, 1992). Because the packing arrangements of stacked duplexes in the two different space groups showed close resemblance, the local helix parameters were virtually identical. Conversely, more extensive deviations in the packing modes between two lattices triggered changes in the loca ...
... Heinemann & Hahn, 1992). Because the packing arrangements of stacked duplexes in the two different space groups showed close resemblance, the local helix parameters were virtually identical. Conversely, more extensive deviations in the packing modes between two lattices triggered changes in the loca ...
Oxidized and Reduced Azotobacter Vinelandii
... Synthetic inorganic complexes have been characterized at atomic resolution as analogues of [2Fe-2S], [3Fe-4S], and [4Fe-4S] protein-bound clusters (1). These include a large number of compounds with thiolate ligands and [Fe2S2]2+/1+ and [Fe4S4]2+/1+ cores (16) as well as trinuclear cuboidal and hete ...
... Synthetic inorganic complexes have been characterized at atomic resolution as analogues of [2Fe-2S], [3Fe-4S], and [4Fe-4S] protein-bound clusters (1). These include a large number of compounds with thiolate ligands and [Fe2S2]2+/1+ and [Fe4S4]2+/1+ cores (16) as well as trinuclear cuboidal and hete ...
Minerals and Mineral Groups
... Minerals are everywhere! Figure 1.1 shows some common household items and the minerals used to make them. The salt you sprinkle on food is the mineral halite. Silver in jewelry is also a mineral. Baseball bats and bicycle frames both contain minerals. Although glass is not a mineral, it is produced ...
... Minerals are everywhere! Figure 1.1 shows some common household items and the minerals used to make them. The salt you sprinkle on food is the mineral halite. Silver in jewelry is also a mineral. Baseball bats and bicycle frames both contain minerals. Although glass is not a mineral, it is produced ...
BARIUM NITRATE
... Only a small fraction of Bk–249 is obtained by the above reaction because neutrons also induce fission. Alternatively, uranium–238 may be converted to Bk–249 by very short but intense neutron bombardment followed by five successive beta decays. Chemical Properties The chemical properties of berkeliu ...
... Only a small fraction of Bk–249 is obtained by the above reaction because neutrons also induce fission. Alternatively, uranium–238 may be converted to Bk–249 by very short but intense neutron bombardment followed by five successive beta decays. Chemical Properties The chemical properties of berkeliu ...
Identification and Determination of Crystal Structures and
... (c) are given in (b) and (d) in Fig. 2.1. The size of centred unit cell is twice that of the primitive cell. Consequently, the reciprocal lattice generated by the centred cell is twice denser than that obtained from the primitive cell. Note that the unit vectors of the centred cell are mutually perp ...
... (c) are given in (b) and (d) in Fig. 2.1. The size of centred unit cell is twice that of the primitive cell. Consequently, the reciprocal lattice generated by the centred cell is twice denser than that obtained from the primitive cell. Note that the unit vectors of the centred cell are mutually perp ...
3 Minerals
... all naturally occurring elements. The elements are arranged in rows, with increasingly heavier elements to the right and bottom. This table is commonly called the periodic chart. The distinguishing feature of an element is the number of protons in the nucleus of each of its atoms, often called the a ...
... all naturally occurring elements. The elements are arranged in rows, with increasingly heavier elements to the right and bottom. This table is commonly called the periodic chart. The distinguishing feature of an element is the number of protons in the nucleus of each of its atoms, often called the a ...
Calcium Ion Exchange in Crystalline Gelsolin
... of G2 followed by a sequence of contacts with actin that pry open the G1-G3 latch.5 In spite of the absence of strict regulation of the actin filament-severing ability of G1-G3, calcium ion binding to this fragment does influence its structure and activity, as demonstrated by a reduced hydrodynamic ...
... of G2 followed by a sequence of contacts with actin that pry open the G1-G3 latch.5 In spite of the absence of strict regulation of the actin filament-severing ability of G1-G3, calcium ion binding to this fragment does influence its structure and activity, as demonstrated by a reduced hydrodynamic ...
The Crystal Structure and Genesis of the Gold
... within the University of Colorado’s mineral collection. Structurally, krennerite is the most ordered of these three species. Single crystal structural studies yielded several datasets, including a refinement of the krennerite structure with a reliability factor of 0.024- a significantly lower value ...
... within the University of Colorado’s mineral collection. Structurally, krennerite is the most ordered of these three species. Single crystal structural studies yielded several datasets, including a refinement of the krennerite structure with a reliability factor of 0.024- a significantly lower value ...
research papers
... Towards accurate structural characterization of metal centres in protein crystals: the structures of Ni and Cu T6 bovine insulin derivatives Using synchrotron radiation (SR), the crystal structures of T6 bovine insulin complexed with Ni2+ and Cu2+ were solved to 1.50 and 1.45 Å resolution, respecti ...
... Towards accurate structural characterization of metal centres in protein crystals: the structures of Ni and Cu T6 bovine insulin derivatives Using synchrotron radiation (SR), the crystal structures of T6 bovine insulin complexed with Ni2+ and Cu2+ were solved to 1.50 and 1.45 Å resolution, respecti ...
Metal ions bound at the active site of the junctionresolving enzyme
... Pyrococcus (Nishino et al., 2001), the putative active sites contain clusters of acidic side chains that probably constitute metal ion-binding sites. A calcium ion was observed bound to the active site of T4 endonuclease VII (Raaijmakers et al., 1999). We have recently presented the crystal structur ...
... Pyrococcus (Nishino et al., 2001), the putative active sites contain clusters of acidic side chains that probably constitute metal ion-binding sites. A calcium ion was observed bound to the active site of T4 endonuclease VII (Raaijmakers et al., 1999). We have recently presented the crystal structur ...
Sample pages
... 1.1.6.1. Continuous Fourier transform .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 1.1.6.2. Discrete Fourier transform .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 1.1.6.3. Bloch’s theorem .. .. .. .. .. .. .. .. .. .. .. .. .. .. ...
... 1.1.6.1. Continuous Fourier transform .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 1.1.6.2. Discrete Fourier transform .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 1.1.6.3. Bloch’s theorem .. .. .. .. .. .. .. .. .. .. .. .. .. .. ...
Chapter 2 Lecture PowerPoint Handout
... • An isotope is an atom that exhibits variation in its mass number (same # protons with different # neutrons) • Some isotopes have unstable nuclei that emit particles and energy in a process known as radioactive decay ...
... • An isotope is an atom that exhibits variation in its mass number (same # protons with different # neutrons) • Some isotopes have unstable nuclei that emit particles and energy in a process known as radioactive decay ...
Crystal Structure of the 23S rRNA Fragment Specific to r
... All our attempts to obtain crystals of HmaL1 or its complexes with specific rRNA fragments failed, possibly owing to the anomalous negative charge of this protein. Therefore, having started from the known structures of L1 proteins from other organisms we built a model of HmaL1 and refined it by mole ...
... All our attempts to obtain crystals of HmaL1 or its complexes with specific rRNA fragments failed, possibly owing to the anomalous negative charge of this protein. Therefore, having started from the known structures of L1 proteins from other organisms we built a model of HmaL1 and refined it by mole ...
Crystal structure of boron-rich metal borides

Metals, and specifically rare-earth elements (RE), form numerous chemical complexes with boron. Their crystal structure and chemical bonding depend strongly on the metal element M and on its atomic ratio to boron. When B/M ratio exceeds 12, boron atoms form B12 icosahedra which are linked into a three-dimensional boron framework, and the metal atoms reside in the voids of this framework. Those icosahedra are basic structural units of most allotropes of boron and boron-rich rare-earth borides. In such borides, metal atoms donate electrons to the boron polyhedra, and thus these compounds are regarded as electron-deficient solids.The crystal structures of many boron-rich borides can be attributed to certain types including MgAlB14, YB66, REB41Si1.2, B4C and other, more complex types such as RExB12C0.33Si3.0. Some of these formulas, for example B4C, YB66 and MgAlB14, historically reflect the idealistic structures, whereas the experimentally determined composition is nonstoichiometric and corresponds to fractional indexes. Boron-rich borides are usually characterized by large and complex unit cells, which can contain more than 1500 atomic sites and feature extended structures shaped as ""tubes"" and large modular polyhedra (""superpolyhedra""). Many of those sites have partial occupancy, meaning that the probability to find them occupied with a certain atom is smaller than one and thus that only some of them are filled with atoms. Scandium is distinguished among the rare-earth elements by that it forms numerous borides with uncommon structure types; this property of scandium is attributed to its relatively small atomic and ionic radii. Crystals of the specific rare-earth boride YB66 are used as X-ray monochromators for selecting X-rays with certain energies (in the 1–2 keV range) out of synchrotron radiation. Other rare-earth borides may find application as thermoelectric materials, owing to their low thermal conductivity; the latter originates from their complex, ""amorphous-like"", crystal structure.