Gas-Phase Reactions of Homo- and ... - Institut für Chemie

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Helvetica Chimica Acta ± Vol. 88 (2005)
Table 5. Reactions of the Homo- and Heteronuclear Cluster Cations MM' ‡ (M, M' ˆ Fe, Co, Ni) with Butane-, Propane-,
and Ethanenitrile, Respectively
Ni ‡ ‡ [NiC 4H 7N] 2% (41)
[Ni 2C 4H 5N] ‡ ‡ H 2 57% (42)
[Ni 2C 4H 3N] ‡ ‡ 2H 2 28% (43)
Ni ‡ 2 ‡ n-C 3H 7CN [NiC 4H 7N] ‡ ‡ Ni 4% (44)
[Ni 2C 2H 3N] ‡ ‡ C 2H 4 8% (45)
[Ni 2C 3H 4] ‡ ‡ H 2 ‡ HCN 1% (46)
S k ˆ 2.07 ´ 10 9 cm 3 s 1
f ˆ 0.62
[Ni2C3H5N] ‡ 7% (47)
Ni ‡ ‡ [NiC3H5N] 13% (48)
Ni ‡ 2 ‡ C2H5CN [Ni2C3H3N] ‡ ‡ H2 20% (49)
[NiC3H5N] ‡ ‡ Ni 35% (50)
[Ni2CHN] ‡ S k ˆ 1.38 ´ 10
‡ C2H4 25% (51)
9 cm3 s 1
f ˆ 0.39
Ni ‡ ‡ [NiC 2H 3N] 12% (52)
Ni ‡ 2 ‡ CH 3CN [NiC 2H 3N] ‡ ‡ Ni 77% (53)
[Ni 2CN] ‡ ‡ CH 3 11% (54)
S k ˆ 1.27 ´ 10 9 cm 3 s 1
f ˆ 0.32
[FeNiC 4H 7N] ‡ 25% (55)
FeNi ‡ ‡ n-C 3H 7CN [FeNiC 4H 5N] ‡ ‡ H 2 40% (56)
[NiC 4H 7N] ‡ ‡ Fe 35% (57)
S k ˆ 9.34 ´ 10 10 cm 3 s 1
f ˆ 0.25
[CoNiC 4H 5N] ‡ ‡ H 2 53% (58)
CoNi ‡ ‡ n-C 3H 7CN [NiC 4H 7N] ‡ ‡ Co 43% (59)
[CoNiC 2H 3N] ‡ ‡ C 2H 4 4% (60)
S k ˆ 1.83´ 10 9 cm 3 s 1
f ˆ 0.48
[CoNiC3H5N] ‡ < 4% (61)
CoNi ‡ ‡ C2H5CN [NiC3H5N] ‡ ‡ Co
[CoNiCHN]
80% (62)
‡ S k ˆ 1.55 ´ 10
‡ C2H4 16% (63)
9 cm3 s 1
f ˆ 0.38
CoNi ‡ ‡ CH3CN [NiC2H3N] ‡ ‡ Co 100% (64)
k ˆ 1.74 ´ 10 10 cm 3 s 1
f ˆ 0.38
FeCo ‡ . This conclusion is supported by the, though limited, thermochemical data
available for the naked clusters Fe ‡ 2 ,Co ‡ 2 , FeCo ‡ , and Ni ‡ 2 : the dissociation energies of
D 0(Fe ‡ Fe) ˆ 262 7kJ mol 1 [27], D 0(Co ‡ Co) ˆ 265 10 kJ mol 1 [28], and
D 0(Co ‡ Fe) ˆ 276 29 kJ mol 1 [29] 2 ) well exceed that of D 0(Ni ‡ Ni) ˆ 201 7kJ
mol 1 [30]; for FeNi ‡ and CoNi ‡ , the corresponding energies are unknown. Further, in
2 ) D0(Fe ‡ Co) is nearly identical to D0(Co ‡ Fe) due to the small difference in the ionization energies of
Fe and Co; see Footnote 21 of [29].