The 1 : 1 adducts of silver( 1) halides (AgX; X = C1, Br or I) with tricyclohexylphosphine have been prepared and their room-temperature single-crystal structures, solid-state cross polarization magic angle spinning (CP MAS) 3 1 P NMR, solution 31P NMR and far-IR spectra determined. The solid-state structures of the chloride and bromide complexes recrystallized from pyridine arc unsolvated, isomorphous, centrosymmetric dihalidebridged dimers, [.(AgX[P(C,H 1)3] ,I, with three-co-ordinate metal centres. Crystals are triclinic, space group

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The structures of the silver([) complexes [AgBr(PPh,),] and [Ag,X2(PPh,),]*2CHCI, (X = CI or Br) have been determined by single-crystal X-ray diffraction. The complex [AgBr( PPh,),] crystallizes in the monoclinic space group C2/c and contains discrete monomeric [AgBr( PPh,),] units with essentially trigonal-planar AgBrP, co-ordination, and a crystallographic two-fold axis of symmetry coincident with

A series of monomeric [AgX(P(C,H, complexes have been prepared for X = CN, I, Br, C1, SCN, NCO, NO, or CIO, and characterized by single-crystal X-ray determinations, solid-state cross polarization magic angle spinning (CP MAS) ,'P NMR, solution 31P NMR and far-infrared spectroscopy. For X = CN, I, Br, C1 or SCN the crystal structures are isomorphous, crystallizing in a monoclinic C2jc cell with a z 17, b = 9.3, c' z 25 A. p z 1 lo", 2 = 4; the SCN complex exhibits anion disorder/space group ambiguity. For X = NCO or NO, (redetermined) the structures are isomorphous with the previously studied perchlorate, crystallizing in a triclinic P I cell derivative of the C2jc array with a z 9.3, b e 9.8, c = 23 A, CX z 95, p = 96, y z 116". The Ag-P bond lengths correlate inversely with the P-Ag-P angles and depend on the donor properties of the anion X, with, however, a reverse trend noted for the halide complexes. The solid-state CP MAS ,'P NMR spectra show splitting due to 'J(P-Ag) coupling which progressively increases from 322 Hz for X = CN to 505 Hz for X = C10,. For the triclinic species further splitting is observed and assigned to 'J(P-P) coupling between the crystallographically inequivalent phosphorus atoms. These NMR results are consistent with the structural results except for the chloride and perchlorate systems where experiments suggest that both triclinic and monoclinic phases co-crystallize in proportions which depend on the recrystallization procedures. Solution 'lP NMR spectra show doublets assignable to 1 : 2 species. For X = Br, C1, NCO or SCN signals assignable to 1 : 1 species are also observed. Comparison with solid-state data show differences in 'J(P-Ag) that are ascribed to differences in B(P-Ag-P) in the solution and solid states. Far-IR spectra of the halide and pseudo-halide complexes in the series exhibit single bands due to v(AgX) vibrational modes at 207, 149, 121 for X = C1, Br or I and at 288, 241 and 174 cm-' for X = CN, NCO or SCN, these latter results providing rare data for the vibrational frequencies of terminal Ag-C, Ag-N and Ag--S bonds.

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Synthetic, spectroscopic, and single-crystal X-ray structural studies of diverse complexes of silver(I) acylpyrazolonate salts AgQ(R') (QH = 1-phenyl-3-methyl-4-R'(C=O)-pyrazol-5-one; Q(1), R = Ph; Q(2), R' = CF(3); Q(3), R' = Me) with neutral ligands L = unidentate PR(3) (R = Ph, o-tolyl, cyclohexyl) and Hmimt (1-methyl-2-mercaptoimidazole) and bidentate dppe (Ph(2)P(CH(2))(2)PPh(2)) and trimen (N,N,N'-trimethylethylenediamine) define the donor capability of the anionic Q(R') ligand in a variety of roles. In the free ligand Q(3)H (which crystallizes in the monoclinic space group C2/c (no. 15), Z = 8, unit cell parameters a = 17.981(6) A, b = 5.0641(4) A, c = 24.271(6) A, and beta = 99.67(2)), the acidic OH group hydrogen-bonds intramolecularly to the adjacent pyrazolone oxygen, i.e., the two oxygen atoms are cis, true of the other Q(R') species structurally characterized here in their anionic complexed forms, in which they chelate the silver in the usual beta-diketonate manner, but not of the free anion, found in the array [Ag(Ph(3)P)(Hmimt)(2)](Q(1)) (triclinic space group P(-)1(no. 2), Z = 2, unit cell parameters a = 11.553(1) A, b = 11.943(1) A, c = 15.479(2) A, alpha = 74.829(2), beta = 76.094(2), and gamma = 78.185(2)), or [Ag(trimen)Q(1)] (monoclinic space group P2(1)/c (no. 14), Z = 4, unit cell parameters a = 7.982(1) A, b = 12.299(2) A, c = 21.507(3) A, and beta = 95.119(3)), which forms an infinite one-dimensional polymer string, Q(1) linking successive silver(I) atoms by coordination by way of the unsubstituted nitrogen and the pyrazolonate oxygen. In all [Ag(R(3)P)(2)(chelate-Q(1))] (R = Ph, Cy) complexes, P(2)Ag(O,O') arrays are found (R = Ph, monoclinic space group C2/c (no. 15), Z = 8, unit cell parameters a = 16.193(8) A, b = 13.859(7) A, c = 39.306(7) A, and beta = 100.02(3); R = Cy, triclinic space group P(-)1(no. 2), Z = 2, unit cell parameters a = 10.4655(9) A, b = 12.079(1) A, c = 22.804(2) A, alpha = 104.872(2), beta = 95.180(2), and gamma = 104.144(2)), also true of [Ag(Ph(3)P)(2)(O,O'-Q(2))] (triclinic space group P(-)1(no. 2), Z = 2, unit cell parameters a = 10.672(2) A, b = 10.710(2) A, c = 18.713(3) A, alpha = 87.573(2), beta = 80.972(2), and gamma = 81.734(2)), whereas [Ag(o-tol(3)P)Q(1)] (monoclinic space group P2(1)/c (no. 14), Z = 2 dimers, unit cell parameters a = 11.8221(6) A, b = 13.2601(6) A, c = 20.5141(10) A, and beta = 91.758(1)) exists as a dinuclear species containing two AgO(2)NP units where the acylpyrazolonate is coordinated in a bridging O,O'-Q-Nfashion. Silver atoms are four-coordinate in all except the Hmimt complex.

Indonesia is the fifth largest cocoa-producing country in the world, and an increase in cocoa farming efficiency can help farmers to increase their per capita income and reduce poverty in rural areas of this country. This research evaluated the efficiency of Indonesian cocoa farms using a non-parametric approach. The results revealed that the majority of cocoa farms are operated relatively inefficiently. The average technical and allocative efficiencies (0.82 and 0.46, respectively) of these cocoa farms demonstrated that there is potential for improvement. The potential cost reductions range from 36 to 76%, with an average of 60%, if farmers practice efficiently. The technical and allocative efficiencies and cocoa farm economies are affected by the use of quality seeds, organic fertilizers, frequency of extension and training of farm managers, access to bank credit and the market, the participation of women, and the farm manager’s gender. An increase in the output would increase farmers’ income and reduce poverty in rural areas. This research suggests that the availability of extension and training provided to farmers as well as support for women farmer groups should be increased. Credit programs are also important for cocoa farmers, so policymakers should develop programs that make production credit more accessible for farmers, especially through cooperatives and banks.