Noncovalently Connected Framework Assembled from Unusual Octamolybdate-Based Inorganic Chain and Organic Cation

An octamolybdate-containing noncovalently assembled framework with the formula (Hcpy)3[Ag(β-Mo8O26)] (1) (cpy = 4-(5-chloropyridin-2-yl)pyridine) is synthesized and characterized. Compound 1 comprises a three-dimensional supramolecular network constructed from one-dimensional {[Ag(β-Mo8O26)]3−}∞ anionic chains and protonated cpy cationic layers. The inorganic chain only constructed by the building block [β-Mo8O26]4− linked only via a single Ag+ ion is unusual. The extensive and efficient face-to-face π···π interaction in these aromatic N-heterocyclic systems is facilitated by the neighboring electron-withdrawing chlorine atom. Anionic shape and size also play an important role in the resulting supramolecular arrangement

Noncovalently Connected Framework Assembled from Unusual Octamolybdate-Based Inorganic Chain and Organic Cation

An octamolybdate-containing noncovalently assembled framework with the formula (Hcpy)3[Ag(β-Mo8O26)] (1) (cpy = 4-(5-chloropyridin-2-yl)pyridine) is synthesized and characterized. Compound 1 comprises a three-dimensional supramolecular network constructed from one-dimensional {[Ag(β-Mo8O26)]3−}∞ anionic chains and protonated cpy cationic layers. The inorganic chain only constructed by the building block [β-Mo8O26]4− linked only via a single Ag+ ion is unusual. The extensive and efficient face-to-face π···π interaction in these aromatic N-heterocyclic systems is facilitated by the neighboring electron-withdrawing chlorine atom. Anionic shape and size also play an important role in the resulting supramolecular arrangement

Synthesis of Hybrid Phosphomolybdates and Application as Highly Stable and Effective Catalyst for the Reduction of Cr(VI)

Three hybrid phosphomolybdates were successfully synthesized by hydrothermal method and characterized by a series of physicochemical analysis techniques. X-ray single-crystal structural analysis revealed that three compounds with the reductive polyanionic clusters (MoV) were wrapped by protonated organic component bpp cations (bpp = 1,3-bi­(4-pyridyl)­propane) through the complex supramolecular hydrogen bonding network. They also have similar molecular formulas: (H2bpp)3[PbM­(H2O)2]2H6{M­[Mo6O12(OH)3(HPO4)3(PO4)]2}2·nH2O (M = Fe in 1, Zn in 2, n = 4; or M = Mn in 3, n = 6). The oxidation states of all Mo centers in these polyanions are in the form of +5, presenting clusters with the higher negative charge. The feature showed that they were easy to be modified by transition metal and organic moieties, so as to form a high-dimensional structure and produce functional materials with specific properties. Comparison of catalytic ability of three crystals to reduce CrVI using formic acid as reductant, found that crystal 1 was effectively active to this redox reaction. The conversion of CrVI can reach 99% after 120 min of heating in 55 °C water bath, and the conversion of above 95% can still be achieved after 5 recycles of applications

Unusual Oxidation of an N-Heterocycle Ligand in a Metal−Organic Framework

An in situ ligand reaction from the pyridine cycle to −COO- in the copper−organic framework is achieved under hydrothermal conditions. Compound [Cu2(bpa)4] [1; bpa = 5-(4-bromophenyl)picolinic acid] exhibits a one-dimensional chain architecture based on weak Cu−O interactions. The mechanism of ligand transformation is discussed

Unusual Oxidation of an N-Heterocycle Ligand in a Metal−Organic Framework

An in situ ligand reaction from the pyridine cycle to −COO- in the copper−organic framework is achieved under hydrothermal conditions. Compound [Cu2(bpa)4] [1; bpa = 5-(4-bromophenyl)picolinic acid] exhibits a one-dimensional chain architecture based on weak Cu−O interactions. The mechanism of ligand transformation is discussed

The Adjusted R-Square versus <i>k/N</i> and slope versus <i>k/N</i> for the linear fits in <b>Figure 8</b>.

<p>The Adjusted R-Square versus <i>k/N</i> and slope versus <i>k/N</i> for the linear fits in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0058270#pone-0058270-g008" target="_blank"><b>Figure 8</b></a>.</p

Schematic defining the tangential force.

<p> is the component force perpendicular to the wall of the gate. is the component force parallel to the wall. The integral of over time t is the tangential momentum. here in the figure is the same as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115463#pone.0115463.e009" target="_blank">equation (1</a>).</p

Snapshots of the experiment (blurred for privacy protection).

<p>The left panel shows the venue with the participants in the moving circling when there is an obstacle (lower right corner). The trash bin with three participants pushing outside the gate was used to ensure the gate did not collapse. The right panel shows the escape process, when the participants formed a pushing arc at the gate.</p

GA-Optimized obstacle settings for 80 participants.

<p>The obstacle settings are the coordinate positions of the obstacle(s) in the room. No. and R represent the number and radius of the obstacles, respectively. The two numbers in each parenthesis represent the position of one obstacle, thus in the cases of 1, 2 and 3 obstacles, there are 1, 2 and 3 parentheses, respectively.</p><p>GA-Optimized obstacle settings for 80 participants.</p

The friend number’s effects on the average successful trading ratio, market clustering degree and simple social entropy.

<p>With an increase in the number of friends per agent <i>k/N</i>, this model shifts from no information sharing to more information sharing. This figure shows that as <i>k/N</i> increases from 0 to 0.99, the averages of the successful trading ratio <i>D_t</i> and the degree of clustering <i>C_t</i> increase, and the average simple social entropy <i>E_t</i> decreases. The error bars are also shown. All of the averages are calculated after the first 10,000 time-steps.</p