Nickel Ni P

Marton and Schlesinger (15) studied the nucleation and growth of electrolessly deposited thin nickel (Ni-P) films. These studies were later extended and complemented... 

Schlesinger and Marton (15) studied the nucleation and growth of electrolessly deposited thin nickel (Ni-P) films. These studies were later extended and complemented by the studies performed by Cortijo and Schlesinger (19, 20) on radial distribution functions (RDFs). RDF curves were derived from electron diffraction data obtained from similar types of films as well as electrolessly deposited copper ones. Those studies, taken together, have elucidated the process of crystallization in the electroless deposition of thin metal films. 

Providing pseudo-first order conditions are employed, i.e. the initial concentration of aquo-nickel [Ni ] p [PADAD-p and... 

Nickel-based aUoys have superior corrosion resistance to Hon-based aUoys. The only aUoys recommended for hot hydrochloric acid use are Ni—Mo aUoys containing 60—70% Ni and 25—33% Mo. Chlorimet (63 Ni, 32 Mo, 3 Fe) and HasteUoy (60 Ni, 28 Mo, 6 Fe) are found to be stable at aU acid concentrations in the absence of aH and Hon chlorides. Electroless nickel, a Ni—P aUoy containing 2—10% P, shows exceUent resistance to hot hydrogen chloride (71). The corrosion resistance increases with phosphoms content. This coating can be deposited on cast Hon, wrought Hon, mild steel, stainless steels, brass, bron2e, and aluminum (qv). 

Phosphides. Compounds of phosphoms containing the more electropositive elements are generally called phosphides. A large number of binary phosphides as well as many ternary mixed-metal phosphides, metal phosphide nitrides, etc, are known. Some binary phosphides, such as those of nickel, exhibit a variety of stoichiometries (Ni P, Ni P2, Nq2P5, Ni2P, Ni P, NiP, NiP2, NiP ), whereas others, such as aluminum, form only one (AlP). Metalloids such as B and Si also form phosphides. 

In Ni—P electroless deposits, there can be as much as 10% by weight of phosphoms. The amount depends on the added complexing agents and the pH. The Ni—P deposits are fine-grained supersaturated soHd solutions, which may be precipitation hardened by heat treatment to form dispersed Ni P particles in a nickel matrix. 

The engineering properties of electroless nickel have been summarhed (28). The Ni—P aHoy has good corrosion resistance, lubricity, and especiaHy high hardness. This aHoy can be heat-treated to a hardness equivalent to electrolytic hard chromium [7440-47-3] (Table 2), and the lubricity is also comparable. The wear characteristics ate extremely good, especiaHy with composites of electroless nickel and silicon carbide or fluorochloropolymers. Thus the main appHcations for electroless nickel are in replacement of hard chromium (29,30). 

This method is used for the determination of total chromium (Cr), cadmium (Cd), arsenic (As), nickel (Ni), manganese (Mn), beiylhum (Be), copper (Cu), zinc (Zn), lead (Pb), selenium (Se), phosphorus (P), thalhum (Tl), silver (Ag), antimony (Sb), barium (Ba), and mer-cuiy (Hg) stack emissions from stationaiy sources. This method may also be used for the determination of particulate emissions fohowing the procedures and precautions described. However, modifications to the sample recoveiy and analysis procedures described in the method for the purpose of determining particulate emissions may potentially impacl the front-half mercury determination. 

The corrosion rate of amorphous Ni-P alloys in 1 n HCl is lower than those of crystalline nickel metal and amorphous Fe-P-C alloy by factors of about 5 and 250, respectively, and is further decreased by the addition of various elements (Fig. 3.73). 

Fig. 3.73 Average corrosion rates of amorphous Ni-P alloys measured in 1 n HCl at 30°C. Included are average corrosion rates of crystalline nickel and nickel-base alloys ...

The force constants of the Ni—P bond in P " nickel carbonyl complexes increase in the order MeaP < PHg < P(OMe)a < PFs. This order is different from that of the donor-acceptor character, as estimated from uco-The lengthening of the P—O bond of triphenylphosphine oxide upon complexation with uranium oxide has been estimated by i.r. spectroscopy. However, A -ray diffraction shows little difference in the P-O bond lengths (see Section 7). Some SCF-MO calculations on the donor-acceptor properties of McaPO and H3PO have been reported. 

The Ni—P bond is one of the basic motifs in Ni-based catalysis and Ni organometallic chemistry. The earlier work on phosphine-nickel complexes has been reviewed.636 The complex [Ni(dppm)Cl2] with the Ph2PCH2PPh2 (dppm) ligand is square planar. Complexes of formula... 

Reduction of Ni11 chloride complexes [NiCl2(L)] (L = various diphosphinomethanes, -ethanes, and -propanes) with, for example, potassium naphthalenide in THF gives the corresponding Ni1 chlorides [NiCl(L)].2368 By treatment of (963) with LiNHAr, a terminal amido complex of Ni1 (964) was prepared (Scheme 13).2369 It contains planar three-coordinate nickel and a planar amido ligand with d(Ni—N) = 1.881(2) A. The P,Ni,P and C,N,H planes are orthogonal with a 91° dihedral angle. 

The orange, air-stable, homoleptic tetrakis( 71-phosphabenzene)nickel (1046) is tetrahedral (point symmetry 54) and can be obtained from phosphabenzene and [Ni(cod)2].2 25 It features a short Ni—P bond length of 2.1274(5) A with considerable N i P 7r-backbonding and a i/(Ni—P) stretch at 168 cm-1. In solution, partial dissociation of one phosphabenzene ligand is observed. 2-Diphenylphosphino-3-methylphosphinine forms with [Ni(cod)2] in the presence of the CO the dinuclear complex (1047) with a W-frame structure.2526... 

Salvaga and Cavallotti [43], and Randin and Hintermann [44] advanced a metal hydroxide mechanism which involved hydrolyzed nickel ions as the actual nickel reactant in Ni-P deposition ... 

The square-planar complex (34) NiCI2-(P-/i-Bu3)2 was a better catalyst than the tetrahedral complex NiBr2 (PPh3)2 for hydrosilation of styrene with trichlorosilane at temperatures of 150°-170°C. A nickel(0) complex, Ni[P(OPh)3]4, was as good as NiCl2(NC5H5)4, which was best among known nickel catalysts for this reaction. Addition of copper(I) chloride... 

Nickel phosphorus (Ni-P) alloy deposition, 9 691-693. See also Ni-P entries Nickel phosphorus compounds, 17 124... 

Ni-P adhesion, 9 705. See also Nickel phosphorus entries Ni-P alloys, solderability, 9 707, 708 NIPAm hydrogels, 13 738 Ni-P density, 9 705 Ni-P electrical resistivity, 9 706 Ni-P ferromagnetic properties, 9 706 Nipkow disk, 16 484 Ni-P mechanical properties, 9 706 Niranium N/N, base-metal dental alloy, 8 309t... 

Silver, A. and Millar, M. (1992) Synthesis and structure of a unique nickel-thiolate dimer, [(RS)Ni(p.-2-SR)3Ni(SR)] - an example of face-sharing bitetrahedra. J. Chem. Sac. Chem. Commun., 1992, 948-9. 

Nickel phosphate (3Ni + 2P —> Ni P ) is a greenish powder used in electroplating. 

A comparative smdy of great practical value has been carried out between several Ni-based diffusion barrier properties. Those were produced by means of electroless deposition from nickel sulfate and nickel sulfamate deposition solutions (73). It was concluded on the basis of Auger depth profiling (see Section 13.3) that Ni(P) sulfamate has much better diffusion barrier properties than Ni(P) sulfate. This conclusion is a telling example of the influence of anions on the physical properties of electro-chemically deposited metals. 

Diffusion barriers are coatings that serve in that role specifically, protection against undesirable diffusion. One of the best examples is that of a 100- tm-thick electrode-posited copper layer that serves as an effective barrier against the diffusion of carbon. Another example is that of nickel and nickel alloys (notably, electrolessly deposited Ni-P) that block diffusion of copper into and through gold overplate. This is achieved by the deposition of a relatively thin Ni-P layer (less than 1 /mm) between the copper and its overlayer. Naturally, the effectiveness of the diffusion barrier increases with its thickness. Other factors in the effectiveness of a diffusion barrier... 

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