Includes Co2+, Ni3+. :Octahedral low-spin:1 unpaired electron, paramagnetic, substitutionally labile. Includes Co2+, Ni3+. Example: [Co(NH3)6]2+. ;d8:Octahedral high-spin: 2 unpaired electrons, paramagnetic, substitutionally labile. Includes Ni2+.
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Includes Cr2+, Mn3+. :Octahedral low-spin: 2 unpaired electrons, paramagnetic, substitutionally inert. Includes Cr2+, Mn3+. ;d5: :Octahedral high-spin: 5 unpaired electrons, paramagnetic, substitutionally labile. Includes Fe3+, Mn2+. Example: [Mn(H2O)6]2+.
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Includes Fe2+, Co3+. Example: [CoF6]3−. :Octahedral low-spin: no unpaired electrons, diamagnetic, substitutionally inert. Includes Fe2+, Ni4+. Example: [Co(NH3)6]3+. ;d7: :Octahedral high-spin: 3 unpaired electrons, paramagnetic, substitutionally labile.
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It was speculated that boron and nitride atoms may be substitutionally incorporated into graphite layer.
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For first row transition metal complexes such as Ni2+ and Cu+ also form five-coordinate 18-electron species which vary from square pyramidal to trigonal bipyramidal. :Octahedral high spin: 2 unpaired electrons, paramagnetic, substitutionally labile. :Square planar low spin: no unpaired electrons, diamagnetic, substitutionally inert.
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Example: [Ni(NH3)6]2+. :Tetrahedral high-spin: 2 unpaired electrons, paramagnetic, substitutionally labile. Includes Ni2+. Example: [Ni(Cl)4]2-.
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There were 15 variable sites across the five loci, 12 of which differed substitutionally between the two sequences of 'I'iwi and 'Apapane.
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Trace impurities substitutionally replacing carbon atoms in a diamond's crystal structure, and in some cases structural defects, are responsible for the wide range of colors seen in diamond. Most diamonds are electrical insulators and extremely efficient thermal conductors. Unlike many other minerals, the specific gravity of diamond crystals (3.52) has rather small variation from diamond to diamond.
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In contrast, a high-spin d8 transition metal complex is usually octahedral, substitutionally labile, with two unpaired electrons. Jahn-Teller effect is the geometrical distortion of non-linear molecules under certain situations. Any non-linear molecule with a degenerate electronic ground state will undergo a geometrical distortion that removes that degeneracy. This has the effect of lowering the overall energy.
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The first d electron count (special version of electron configuration) with the possibility of holding a high spin or low spin state is octahedral d4 since it has more than the 3 electrons to fill the non-bonding d orbitals according to ligand field theory or the stabilized d orbitals according to crystal field splitting. ;d4: :Octahedral high-spin: 4 unpaired electrons, paramagnetic, substitutionally labile.
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This kinetic barrier prevents life from bursting into flames at room temperature. Electronic spin states are more complex for transition metals. To understand the reactivity of transition metals, it is essential to understand the concept of d electron configuration as well as high-spin and low-spin configuration. For example, a low-spin d8 transition metal complex is usually square planar substitutionally inert with no unpaired electrons.
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In the crystal, the 'A' sites are occupied by lanthanum and strontium atoms, and the 'B' sites are occupied by the smaller manganese atoms. In other words, the material consists of lanthanum manganite with some of the lanthanum atoms substitutionally doped with strontium atoms. The strontium (valence 2+) doping on lanthanum (valence 3+) introduces extra holes in the valence band and thus increases electronic conductivity. Depending on the x value in La1−xSrxMnO3, the unit cell of LSMO can be rhombohedral, cubic, or hexagonal.
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The key component that enables in situ control of supramolecular architecture via the WLA is the use of hemilabile ligands. Hemilabile ligands are polydentate chelates that contain at least two different types of bonding groups, denoted X and Y (Figure 3). The first group (X) bonds strongly to the metal center, while the other group (Y) is weakly bonding and easily displaced by coordinating ligands or solvent molecules (Z). In this way, the substitutionally labile group (Y) can be displaced from, yet remain available for recoordination to, the metal center.
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Its production mechanism is generally accepted as follows: large nickel atom incorporates substitutionally, then expels a nearby carbon (creating a neighboring vacancy), and shifts in-between the two sites. Although the physical and chemical properties of cobalt and nickel are rather similar, the concentrations of isolated cobalt in diamond are much smaller than those of nickel (parts per billion range). Several defects related to isolated cobalt have been detected by electron paramagnetic resonance and photoluminescence, but their structure is yet unknown. A chromium-related optical center has been detected in diamond after ion implantation and subsequent annealing.
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On the Chinese side, armies from seven military regions were rotated through this area to "touch the tiger's butt", a euphemism for obtaining combat experiences given by Chinese paramount leader, Deng Xiaoping. From 1984 to 1989, at least 14 Chinese armies had been substitutionally committed to the fight in the area (1st, 12th, 13th, 14th, 16th, 20th, 23rd, 26th, 27th, 38th, 41st, 42nd, 47th, and 67th). Besides the use of regular forces, China also armed and trained ethnic resistance groups (especially from the Hmong people) to wage unconventional warfare against the governments of Vietnam and Laos.O'Dowd, p. 70.
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This was shown in a single crystal X-ray diffraction study revealing shortened bond lengths in the heterocyclic portion of the ring suggesting electronic delocalization. The chlorinated carba-closo- dodecaborate anion is an outstandingly stable anion with what has previously been described as “substitutionally inert” B–Cl vertices. While the C-vertex of the boron-based anion can de deprotonated and furthermore react with electrophiles, the B–Cl vertices remain substantially inert. The descriptor closo indicates that the molecule is formally derived (by B-to-C+ replacement) from a borane of stoichiometry and charge [BnHn]2– (n = 12 for known carborane acids).
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Harrison has authored or co-authored a wide range of articles Harrison's research career started with his PhD, which was concerned with developing a quantitative and predictive theory of the electronic states in substitutionally disordered systems. Harrison has furthered the practical use of quantum theory for predictive calculations in materials discovery and optimisation. He has developed methods for robust and efficient calculations on functional materials in which strong electronic interactions are dominant and used them to study processes in previously poorly understood materials such as transition metal oxides, oxide interfaces, and functional materials . In doing so he has made significant contributions to the understanding of catalysis and photocatalysis at surfaces, the stability of polar surfaces, spin dependent transport in low dimensional systems, high temperature magnetism in organic and metal-organic materials and the thermodynamics of energy storage materials .
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