The reaction system composed of triethanolamine (TEA) and tetrathiovanadate in the presence of MeONa (MeOLi)or NaNH
2 was studied to afford vanadium and alkali metal TEA complexes. Complexes {M
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V
6O
6[N(CH
2CH
2O)
2(CH
2CH
2OH)]
6}
2S
6 (M = Na (
1), Li (
2)) contain two cyclic V
(IV) [12]metallacrown-6 cations linked bya polysulfide S
62- anion. Also separated from the reaction system is a novel sodium TEA complex {[Na(TEA)]
2S
6}
n(
3), in which parallel coordination chains [Na(TEA)
+]
n are connected by O-H···S hydrogen bonds forming 3-Dnetwork structure. Variable-temperature conductance of
3 was determined to display semiconductor feature. Thedesulfurization of VS
43- was observed to form S
62- anion and/or S
8 molecule in the synthetic reactions of
1-3.A striking contrast was noted that MoS
42- did not desulfurize in the similar reaction to that of VS
43- with TEA,and a Na/TEA complex containing MoS
42-, (Et
4N)
2[Na
2(
![](/images/entities/mgr.gif)
-TEA)
2(CH
3OH)
2](MoS
4)
2 (
4), was obtained instead.The S···H-O and O···H-O hydrogen bonds play an important role in forming the one- or three-dimensionalstructures for all these complexes by the linkages between clusters and chains. The IR spectrum indicates thestructural similarity of complexes
1 and
2. For complex
4, the Mo=S stretch vibration at 468 cm
-1 showingwidening and slight red-shift and the slight movement of the
1H NMR signals of TEA ligand to downfield areconsidered to be the influence of the S···H-O hydrogen bonds. Variable temperature magnetic susceptibilitydata were collected for complex
1. The effect magnetic moment per V
6 unit varies gradually from 4.04
B at 300K to 6.24
B at 5 K, exhibiting ferromagnetic interaction. Heisenberg-type vector-coupling model and molecularfield approximation were used to treat the interaction between the paramagnetic sites and gave a good fittingresult:
J = 3.97 cm
-1,
J' = 1.99 cm
-1,
g = 1.99, F = 3.64 × 10
-3. Density functional calculation was alsoperformed to complex
1 and its Li, K analogues. The lowest total bonding energy of -874.001 eV was obtainedfor [Na
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V
6(
3-O)
6] complex containing six unpaired electrons, indicating the stability of a V
6 system with sixindependent spins
S =
1/
2. When the alkali metal ion is inserted into the [V
6(
3-O)
6] cavity, the positive valuesof the bonding interaction (
Eb) indicate that the insertion depresses the total energy and that complexes
1 and
2together with K
+ complex may exist. However, the lowest
Eb value of the K
+ complex implies its instability.