Coordination polymers types

Coordination polymer Type of adsorption isotherm Guest sorption... 

The charge densities and compositions of many known solids with VxOy layers were screened for possible charge density matches with M(pyz)x (M = Fe, Co, Ni, Cu, Zn) layers [35, 52], as an aid in the synthesis of new heterometallic multilayered vanadates. Close matches were found with M(pyz)x (M = Fe, Co, Ni) coordination polymers, ranging from 0.022/A -0.053/A, and which might suitably form in the presence of the flexible types of V2O5 layers. For example, Co(pyz) layers of chains in Co(pyz)(V03)2 [53] have a charge density of... 

The reaction of the dinuclear gold(I) amidinate complex, [Au2(2,6-Me2Ph-form)2], with Hg(CN)2 (1 2 stoichiometry) in THF forms a 2D coordination polymer, [Au2(2,6-Me2Ph-form)2]-2Hg(CN)2 2THF, not the expected oxidative-addition product of the type formed vdth the ylides. White crystals and a yellow powder are formed. 

The [Ni(NCS)f,]4 ion is almost perfectly octahedral, with Ni—N distances of around 209.5 pm and N—Ni—N angles around 89.5°. The Ni—N—C and N—C—S entities are practically linear.438,439 In [Ni(NCS)2L2] where L is a R-substituted pyridine, stereochemistry and spin state depend on the type and positions of R.431 While for 2-Me- and 2-Et-pyridine square planar complexes are observed, other pyridins lead to coordination polymers with pseudo-octahedral Ni11 due to N,S-bridging thiocyanate. Ni11 thiocyanato complexes have been studied quite intensively as hosts for inclusion compounds.440"442... 

Special emphasis has been laid on structural studies of Cd compounds with dicarboxylic acids, because these combinations form coordination polymers of differing dimensionalities depending on the carboxylate component and on coligands coordinated to Cd. The simplest compound of this type, namely Cd oxalate CdC204, adopts a 3-D framework structure, with CdOe octahedra linked by oxalate groups.272 Further interesting structures containing Cd, oxalate and other components have been described recently.273,274... 

Two general types of polymer electrolytes have been intensively investigated, polymer-salt complexes and polyelectrolytes. A typical polymer-salt complex consists of a coordinating polymer, usually a polyether, in which a salt, e.g. LiC104, is dissolved. Fig. 5.1(a). Both anions and cations can be mobile in these types of electrolytes. By contrast, polyelectrolytes contain charged groups, either cations or anions, covalently attached to the polymer. Fig. 5.1(h), so only the counterion is mobile. 

Steigerwald and co-workers were the first to use a high-boihng solvent to thermolyse these types of precursors [56]. The complexes M(ER)2 (where M = Zn, Cd, Hg E = S, Se, Te R = organic moiety) can be converted to the corresponding materials in the solid state by pyrolysis [57-62]. But due to their polymeric nature it is difficult to isolate these complexes in pure form [63]. Steigerwald et al. [56] successfully prepared two crystalline complexes of phosphine derivatives of the M(EPh)2 (where M = Zn, Cd, Hg E = S, Se, Te). A coordination polymer was formed by the linkage of bidentate phosphine l,2-bis(diethylphosphino)ethane (DEPE) to M(ER)2 in a 1 2 ratio whereas a dimeric complex was formed with a 1 1 ratio of (DEPE) to M(ER)2. X-ray... 

It has been suggested that the copper acetylides are coordination polymers, with intermolecular interaction between the C C bonds of the acetylides and copper atoms as shown in (XL) (13). The chains may be broken with tertiary phosphines (PR s) to give complexes of the type [CuC -CR(PR 3)]4. The X-ray structure of the complex [CuC CPh(PMe3)]4 has some very interesting and unexpected features (46a)-, see structure (XL). 

This type of dinuclear unit has been reported elsewhere and has been characterized with bis-2-pyridyl-pyrazine or quinoxaline both in Cu [31] and in Ag [32] compounds. However, until now such units have not been used as building blocks (loops) in the construction of coordination polymers, an aspect that is discussed below. Each ligand acts in a bidentate manner with one metal center and as a monodentate system with the other. The two rings that are coordinated to the same metal center are nearly coplanar but the other deviates clearly from this plane. In this way, the structure if this dinuclear unit is very well adapted to the preferred conformation of the free ligand. The relative disposition of the ligands allows the existence of face-to-face n-jt-stacking interactions between the quinoxaline and... 

Not all clathrates are hydrates. Other well-known examples have host lattices formed from hydrogen bonded aggregates of hydroquinone, phenol, and similar organic compounds. Non-hydrogen bonded host structures are also known. One example is a cyclotriphosphazene. (C6H402PN). that traps molecules such as benzene in tunnels in the crystal.2 In addition, coordination polymers are formed by ambidentate ligands, such as CN and SCN, which coordinate to metal ions at both ends (Chapter 12). Perhaps the best known of this type of compound is the series of Ni(CN)2NHj M compounds, where M may be benzene, thiophene, furon. pyrrole, aniline, or phenol. 

Approaches to the formation of three new types of micro-porous materials that complement zeolites will be discussed. In each case, whether metal coordination polymers, metal-linked ceramic oxide clusters, or new hybrids containing both coordination and ceramic components, engineering of the Secondary Building Unit (SBU) is of critical importance. Successful examples of these approaches include the first thermally stable 3-D micro-porous coordination polymer with chemical functionalizability [Cu3(TMA)2(H20)3] , as well as a 3-D micro-porous cluster based material [V,2B18O60H8(Cd(en)(H2O) 3]". ... 

Figure 10.71 Molecular necklace type coordination polymer rotaxanes (a) hexagonal 2D polyrotaxane net and (b) square-grid shaped 2D polyrotaxane net (reproduced by permission of The Royal Society of Chemistry).

---