No abstract

Quantifying habitat use is vital to understanding animal ecology. Herein, we contrast classification‐based (i.e., animal locations are placed into habitat categories for subsequent analyses) and distance‐based (i.e., distance between animal locations and habitat features are used in subsequent analyses) approaches for analyzing habitat use data. Compositional analysis (CA) and a distance‐based analysis (DA) were used to quantify habitat selection of Northern Bobwhite (Colinus virginianus). We qualitatively compared the outcome of these different procedures to illustrate advantages of the DA approach. The DA approach identified edges as an important habitat feature, and location error did not alter conclusions from DA. In contrast, CA did not detect the importance of edge, and presence of location errors altered conclusions. Moreover, modeling the distribution of location error did not effectively reduce sensitivity to error within CA. Distance‐based approaches to habitat analyses are not restricted to linear or point habitat features, require no explicit error handling, and permit extraction of more information from the data than classification‐based analyses alone. Corresponding Editor: J. M. Fryxell

Electronic structure modulation of metal–organic frameworks (MOFs) through the connection of linker “wires” as a function of an external stimulus is reported for the first time. The established correlation between MOF electronic properties and photoisomerization kinetics as well as changes in an absorption profile is unprecedented for extended well-defined structures containing coordinatively integrated photoresponsive linkers. The presented studies were carried out on both single crystal and bulk powder with preservation of framework integrity. An LED-containing electric circuit, in which the switching behavior was driven by the changes in MOF electronic profile, was built for visualization of experimental findings. The demonstrated concept could be used as a blueprint for development of stimuli-responsive materials with dynamically controlled electronic behavior.

Two new one-dimensional organic/inorganic composite polymers were synthesized by the reaction of Cd(NO3)2·4H2O with 1,2-bis(4-pyridyl)ethyne or trans-1,2-bis(4-pyridyl)ethene in several solvent systems. [Cd(NO3)2(1,2-bis(4-pyridyl)ethyne)1.5] n (1), which has an infinite one-dimensional structure with interpenetrating molecular ladders, was obtained by reacting Cd(NO3)2·4H2O with 1,2-bis(4-pyridyl)ethyne in a methylene chloride/methanol solvent system. It crystallized in the monoclinic space group C2/c (No. 15), with a = 20.713(3) Å, b = 17.450(2) Å, c = 14.451(3) Å, β = 129.203(8)°, Z = 8. [Cd(NO3)2(1,2-bis(4-pyridyl)ethene)1.5] n (2) was generated from the reaction of Cd(NO3)2·4H2O with the trans-1,2-bis(4-pyridyl)ethene ligand in an ethanol/water system. It has a novel infinite non-interpenetrating zigzag chain structure which is made up of trans-1,2-bis(4-pyridyl)ethene−Cd−trans-1,2-bis(4-pyridyl)ethene−Cd−trans-1,2-bis(4-pyridyl)ethene building units. Compound 2 crystallized in the triclinic space group P1̄ (No. 2), with a = 10.725(2) Å, b = 10.814(2) Å, c = 9.517(2) Å, α = 104.21(2)°, β = 94.60(1)°, γ = 106.62(1)°, Z = 2. In compound 1, the Cd(II) centers lie in a heptacoordinate environment, while in compound 2, the Cd(II) atoms adopt an octahedral geometry. The two kinds of polymer structures are based on a T-shape and a linear building block, respectively. [Cd(NO3)2(1,2-bis(4-pyridyl)ethane)1.5] n (3) was also synthesized by the reaction of Cd(NO3)2·4H2O with the 1,2-bis(4-pyridyl)ethane ligand in a methylene chloride/methanol system. Polymer 3 forms square units, which are linked through the two Cd(II) centers to give infinite linear chains. The synthesis of compound 3 was reported by Fujita (Fujita, M. J. Chem. Soc., Chem. Commun. 1994, 1977) using a different solvent system.

Cations are crucial components in emerging functional polyelectrolytes for a myriad of applications. Rapid development in this area necessitates the exploration of new cations with advanced properties. Herein we describe a combination of computational and experimental design of cobaltocene metallo-cations that have distinct electronic and redox properties. One of the direct outcomes on the first synthesis of a complete set of cation derivatives is to discover highly stable cations, which are further integrated to construct metallo-polyelectrolytes as anion-exchange membranes in solid-state alkaline fuel cells. The device performance of these polyelectrolytes under highly basic and oxidative environments is competitive with many organo-polyelectrolytes.