Study on the Inert Coordination Compound in the System of“Molybdenum(Ⅵ)—TAE—Hydroxylamine”and its Analytical Application

In the presence of ethyl alcohol or emulsifier OP,molybdenum(Ⅵ) forms 1∶1∶1'water soluble colored coordination com- pound with both of 2-(2-thiazolylazo)-5-diethylaminophenol (abbreviation TAE) and hydroxylamine.This deep blue coordination compound is inert characteristically and remains stable in 1.7 mol/L sulfuric acid,2.4 mol/L hydrochloric or ni- tric acid.It will not be decomposed by masking agents even on boiled,while in that case,almost all the colored coordination com- pounds formed by other metal ions will be decomposed completely.This inert character of the coordination compound of molybdenum(Ⅵ) and its utilization in improving the analytical selectivity have been discussed.In the coexistence of various for- eign ions,especially in the presence of a great quantity of tungsten,which always interferes with the determination of molybdenum,the direct determination of molybdenum in the aqueous solution by applying this system has shown an acceptable sensitivity and reproducibility.From the results of determination in some synthetic and standard samples,it seems feasible to use this system in the determination of molybdenum in nonferrous alloys.

STUDY ON THE COORDINATION COMPOUNDS OF RARE EARTHS WITH DIPEPTIDE-COORDINATION OF RARE EARTHS WITH DL-ALANYL-ALANINE

In this paper protonation constants of the title lisand and stability constants of its coordination compounds with rare earths have been determined by potentiometric titration at 25±0.1℃ and ionic strength of 0.10mol.dm^(-3)NaClO_4. The coordination of rare earths with DL-alanyl-alanine has been discussed. The stability of the coordination compound shows 'tetrad effect'. The position for yttrium shifts from its usual Bo-Er region to the vicinity of Tb.

STUDY ON THE STRUCTURES OF COORDINATION COMPOUNDS OF N-(ortho-METHYL)-AND N-(ortho-METHOXY)-PHENYL IMINODIACETATO-Cu(Ⅱ)

The coordination compounds,{Cu[CH_3C_6H_4N(CH_2COO)_2]}.2H_2O and {Cu[CH_3OC_6H_4N(CH_2COO)_2]}.2H_2O,have been prepared and its crystal struc- tures determined.The final discrepancy factors are R=0.052,R_w=0.061 for (I)and R=0.052,R_w=0.039 for(Ⅱ).The geometry of the coordination poly- hedron with Cu(Ⅱ)is a distorted tetragonal pyramid for(Ⅰ)and an unsym- metrical and extended tetragonal bipyramid for(Ⅱ),respectively.The re- sults of EHMO calculations indicate that the ligand mainly provided the field with very few of its electrons being coordinated to the central atom.

STUDIES ON SOLID STATE REACTIONS OF COORDINATION COMPOUNDS(LXⅡ)Solid state synthesis and crystal structure of the complex ICu_(0.84)Au_(0.16)(PPh_3)_2(SC(Ph)NHPh)CIJ·0.5CS_2

[Cu_(0.84)Au_(0.16)(PPh_3)_2(SC(Ph)NHPh)Cl]·0.5CS_2=,Mr=895.79,monoclinic,space group P2_1/a,a=17.231(3),b=14.611(2),c=18.000(3) ,β=105.56(2)°,V=4365(1) ~3, Z=4,D_c=1.37g/cm^3.,λ(MoK_α)=0.71073 ,μ=12.15cm^(-1),F(000)=1855,R=0.052, R_W=0.045 for 3930 observed reflections with Ⅰ>1.5σ(Ⅰ).The central metal atom has a dis. torted tetrahedral geometry with bond lengths Cu-S=2.384(2) (Au-S=2.389(4)), Cu-Cl=2.481(3)(Au-Cl=2.474(1))and Cu-P=2.269(2)-2.289(2)(Au-P=2.270(4)-2.279(4)) .

Studies on the solid state reactions of coordination conpounds——XLⅤⅢ.The effect of KSCN on the thermal decomposition of cobalt(Ⅲ)-ammine complexes

The evolved gaseous analysis (EGA),infrared spectra,and XRD have been applied to the study of solid state reactions of KSCN with five cobalt(Ⅲ)-ammine complexes:[Co- (NH_3)_5N_3]Cl_2,[Co(NH_3)_5(NO_2)]Cl_2,[Co(NH_3)_5(H_2O)]Cl_3,[Co(NH_3)_5Cl]Cl_2,and [Co(NH_3)_6]Cl_3 in a hydrogen atmosphere.It is found that the existence of KSCN shifts the thermal decom- position of these complexes to a lower temperature.The corresponding peak temperatures are near 140℃.The effect of KSCN is discussed and kinetic parameters of deammine reactions are calculated.