The metal nitride halides, MNX (M ) Ti, Zr; X ) Cl, Br, I), were first reported by Juza and Heners in 1964 along with a high temperature -polymorph for ZrNCl and ZrNBr. 1 Subsequently, Ohashi et al. have shown that an alternative chemical vapor transport synthesis of -ZrNCl and -ZrNBr yields more highly crystalline samples of these compounds. 2, 3 We have recently reported that these host lattices are in fact isostructural with rhombohedral SmSI. 4,5 In this structure each Zr atom is seven-coordinate and is best described as being in a distorted monocapped octahedral arrangement with three halide atoms and three N atoms adopting a facarrangement with a fourth capping nitrogen above the N 3 face. The octahedra are distorted by the displacement of the Zr atom from the center toward the capped N 3 face to such an extent that the Zr and N atoms become essentially coplanar. These monocapped octahedral units are arranged in an edge-sharing manner, forming the XZrNNZrX layer structure (Figure 1).The intercalation of lithium into -ZrNCl was first reported in 1984 and subsequent studies showed that other alkali metals could also be intercalated into this lattice. 6,7 Interest in these compounds was recently increased following reports that they become superconducting at temperatures below 15K. 8,9 In a more recent study, intercalation of lithium ions in the isostructural host lattice -HfNCl was shown to yield Li 0.48 (THF) yHfNCl, which exhibits a superconducting transition temperature of 25.5K. 10 Metallocenes and in particular cobaltocenes have previously been intercalated into a range of host lattices including MX 2 (M ) Ti, Zr, Nb, Ta, Sn; X ) S, Se), 11 MOCl (M ) Fe, V, Ti), 12 MPS 3 (M ) Mn, Cd, Fe), 13 and Zr(HPO 4 ) 2 ‚H 2 O. 14 These intercalates have been widely studied with respect to their structural, electronic, and magnetic properties. In this study we report the metallocene intercalation chemistry of -ZrNCl.-ZrNCl was prepared under conditions reported previously and intercalation was achieved by using excess guest solutions in THF of cobaltocene {Co(Cp) 2 ; Cp ) η-C 5 H 5 }, 1,1′-dimethylcobaltocene {Co(Cp′) 2 ; Cp′ ) η-C 5 H 4 Me}, and decamethylcobaltocene {Co(Cp*) 2 ; Cp* ) η-C 5 Me 5 } at 60°C. 2,3 In each case, complete intercalation was confirmed by the absence of Bragg reflections characteristic of -ZrNCl in the XRD pattern with the stoichiometry of the guest determined by elemental analysis. The characterizing data are summarized in Table 1. As the interlayer separations of the cobaltocene and 1,1′-dimethylcobaltocene are the same and less than that observed for the decamethylcobaltocene intercalate, it can be deduced that the guest molecules are orientated with their principal axes parallel to the host layers. This orientation is the same as has been observed for cobaltocene intercalates of other layered systems and is shown schematically in Figure 1. [15][16][17][18][19] We have also attempted intercalation reactions with other organometallic guests with similar redox potentials, including chro...

The crystal structures of the layered host lattices, b-ZrNBr and b-HfNCl have been determined. They have been found to be isostructural with rhombohedral SmSI. New lithium intercalation compounds (Li x MNX; M=Zr, Hf; X=Cl, Br, I ) have been prepared by treatment of either b-ZrNBr, b-HfNCl, a-ZrNBr or a-ZrNI with an excess of BuLi in hexane. These intercalates are all superconducting and show transition temperatures (T c ) of 12, 20, 11 and 11 K respectively. The lithium intercalates of the host lattices b-ZrNBr, a-ZrNBr and a-ZrNI are the first examples of intercalation into these materials.

While the process of habituation is essential for researchers to observe primates in their natural habitats, ethical dilemmas may arise from its consequences. We collected data from 286 participants via an online survey to investigate: (a) how primatologists perceive their ethical duties toward their subjects; (b) the extent to which primatologists are concerned about the potential ethical consequences of habituation; and (c) the methods primatologists use to reduce potential harms caused by habituation. Overall, primatologists felt an extremely strong duty to mitigate harms that they may cause (e.g., to not stress individuals during observation, treat injuries, and reunite separated individuals) and expressed very high concern for habituation's potential to increase the vulnerability of their subjects to poaching and disease transfer. Ratings for those items were so high that they could not be included in subsequent exploratory factor analyses that were designed to reveal constructs underlying respondents’ ratings of their ethical duties and concerns. Factor analysis of ratings of ethical duties revealed that primatologists reported a strong duty to mitigate harms caused by other humans and a lower perceived duty to mitigate naturally occurring harmful events. Factor analysis on ethical concern ratings revealed that respondents were concerned about harms during the habituation process, the presence of unhabituated behavior after habituation had been established, and indirect harms of habituation. Concerns for unhabituated behavior and indirect harms were rated slightly higher than concern for harms during the habituation process. To mitigate potential harms, primatologists primarily reported engaging in strategies to reduce stress in their subjects. Our findings reveal a disconnect between primatologists' ratings of their ethical concerns and their reported mitigation practices that may, in part, stem from gaps in knowledge about the true impacts of habituation. We suggest areas of discussion and research in the field necessary to address those gaps.

Mol. L'rur. m d Liy.The ordered layered double hydroxide, [LiAI,(OH),]C1.2H20 exhibits shape-selective ion-exchange intercalation of dicarboxylate anions. Specific isomeric preferences can he controlled by varying the reaction temperatures. The intercalated guests can be quantitatively recovered from the host lattice with concomitant regeneration of the host offering a novel approach in separation science. To illustrate the potential of this new material in separation science. we describe the isolation of pure 1,4-henzenedicarhoxylate and 2,8naphthalenedi-carboxylate from mixtures of their isomers. Thc neutral organic acids are both monomers in the synthesis of a range of important polyesters.

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