SOLUTION-LIQUID-SOLID GROWTH OF INDIUM-PHOSPHIDE FIBERS FROM ORGANOMETALLIC PRECURSORS - ELUCIDATION OF MOLECULAR AND NONMOLECULAR COMPONENTS OF THE PATHWAY
Tj. Trentler et al., SOLUTION-LIQUID-SOLID GROWTH OF INDIUM-PHOSPHIDE FIBERS FROM ORGANOMETALLIC PRECURSORS - ELUCIDATION OF MOLECULAR AND NONMOLECULAR COMPONENTS OF THE PATHWAY, Journal of the American Chemical Society, 119(9), 1997, pp. 2172-2181
Methanolysis of {t-Bu(2)In[mu-P(SiMe(3))(2)]}(2) (1) in aromatic solve
nts gives polycrystalline InP fibers (dimensions 10-100 nm x 50-1000 n
m) at 111-203 degrees C. The chemical pathway consists of a molecular
component, in which precursor substituents are eliminated, and a nonmo
lecular component, in which the InP crystal lattices are assembled. Th
e two components working in concert comprise the solution-liquid-solid
(SLS) mechanism. The molecular component proceeds through a sequence
of isolated and fully characterized intermediates: 1 --> [t-Bu(2)In(mu
-OMe)](2) (2) --> [t-Bu(2)In(mu-PHSiMe(3))](2) (3) --> 2 --> [t-Bu(2)I
n(mu-PH2)](3) (4). Complex 4, which is alternatively prepared from t-B
u(3)In and PH3, undergoes alkane elimination, the last steps of which
are catalyzed by the protic reagent MeOH, PhSH, Et(2)NH, or PhCO(2)H.
In the subsequent nonmolecular component of the pathway, the resulting
(InP)(n) fragments dissolve into a dispersion of molten In droplets,
and recrystallize as the InP fibers. Important criteria are identified
for crystal growth of covalent nonmolecular solids from (organic) sol
ution. The outcomes of other solution-phase semiconductor syntheses ar
e rationalized according to the functioning of molecular and nonmolecu
lar pathway components of the kind identified here.