338
J. Handzlik
Modelling of the molybdenum oxide species on silica allowed to support the experimental proposals about their structure. The MoO x /SiO 2 system was also computationally studied as the catalyst for selective oxidation reactions and alkene metathesis.
However, the still unknown mechanism of generation of the metathesis active sites in
this system was not examined, and theoretical studies on this issue would be desired.
Although the WO x /SiO 2 system is an important industrial catalyst for alkene
metathesis, computational works on the metathesis activity of the surface tungsten
oxide species on silica are lacking, only the structure of the W(VI) species was
modelled. Hence, further theoretical investigations of this system are also needed.
Combined with experimental results, computational studies often enabled for better recognizing of the structure of the surface metal species on silica. On the other
hand, many mechanisms of the catalytic reactions, especially the formation of the
active sites from the metal oxide precursors, have not been understood well enough
yet. Applying advanced surface models with representative distribution of metal
sites to determine complex reaction mechanisms and structure–activity relationships
seems to be a challenge for future works. Even more challenging might be an application of ab initio molecular dynamics methods to study catalytic reactions over the
silica-supported metal oxide systems.
References
1. Sautet P, Delbecq F (2010) Catalysis and surface organometallic chemistry: a view from
theory and simulations. Chem Rev 110:1788–1806
2. Handzlik J, Kurleto K (2013) Theoretical investigations of heterogeneous olefin metathesis
catalysts. Curr Org Chem 17:2796–2813
3. Handzlik J, Ogonowski J (2012) Structure of isolated molybdenum(VI) and molybdenum(IV)
oxide species on silica: periodic and cluster DFT studies. J Phys Chem C 116:5571–5584
4. Handzlik J, Grybos R, Tielens F (2013) Structure of monomeric chromium(VI) oxide species
supported on silica: periodic and cluster DFT studies. J Phys Chem C 117:8138–8149
5. Gierada M, Michorczyk P, Tielens F, Handzlik J (2016) Reduction of chromia-silica catalysts:
a molecular picture. J Catal 340:122–135
6. Fong A, Yuan Y, Ivry SL, Scott SL, Peters B (2015) Computational kinetic discrimination of ethylene polymerization mechanisms for the Phillips (Cr/SiO 2 ) catalyst. ACS Catal
5:3360–3374
7. Guesmi H, Tielens F (2012) Chromium oxide species supported on silica: a representative
periodic DFT model. J Phys Chem C 116:994–1001
8. Guesmi H, Grybos R, Handzlik J, Tielens F (2014) Characterization of molybdenum
monomeric oxide species supported on hydroxylated silica: a DFT study. Phys Chem Chem
Phys 16:18253–18260
9. Guesmi H, Grybos R, Handzlik J, Tielens F (2016) Characterization of tungsten monomeric
oxide species supported on hydroxylated silica; a DFT study. RSC Adv 6:39424–39432
10. Floryan L, Borosy AP, Núñez-Zarur F, Comas-Vives A, Copéret C (2017) Strain effect and dual
initiation pathway in Cr III /SiO 2 polymerization catalysts from amorphous periodic models. J
Catal 346:50–56
11. Dapprich S, Komáromi I, Byun KS, Morokuma K, Frisch MJ (1999) A new ONIOM implementation in Gaussian98. Part I. The calculation of energies, gradients, vibrational frequencies
and electric field derivatives. J Mol Struct THEOCHEM 461–462:1–21
J. Handzlik
Modelling of the molybdenum oxide species on silica allowed to support the experimental proposals about their structure. The MoO x /SiO 2 system was also computationally studied as the catalyst for selective oxidation reactions and alkene metathesis.
However, the still unknown mechanism of generation of the metathesis active sites in
this system was not examined, and theoretical studies on this issue would be desired.
Although the WO x /SiO 2 system is an important industrial catalyst for alkene
metathesis, computational works on the metathesis activity of the surface tungsten
oxide species on silica are lacking, only the structure of the W(VI) species was
modelled. Hence, further theoretical investigations of this system are also needed.
Combined with experimental results, computational studies often enabled for better recognizing of the structure of the surface metal species on silica. On the other
hand, many mechanisms of the catalytic reactions, especially the formation of the
active sites from the metal oxide precursors, have not been understood well enough
yet. Applying advanced surface models with representative distribution of metal
sites to determine complex reaction mechanisms and structure–activity relationships
seems to be a challenge for future works. Even more challenging might be an application of ab initio molecular dynamics methods to study catalytic reactions over the
silica-supported metal oxide systems.
References
1. Sautet P, Delbecq F (2010) Catalysis and surface organometallic chemistry: a view from
theory and simulations. Chem Rev 110:1788–1806
2. Handzlik J, Kurleto K (2013) Theoretical investigations of heterogeneous olefin metathesis
catalysts. Curr Org Chem 17:2796–2813
3. Handzlik J, Ogonowski J (2012) Structure of isolated molybdenum(VI) and molybdenum(IV)
oxide species on silica: periodic and cluster DFT studies. J Phys Chem C 116:5571–5584
4. Handzlik J, Grybos R, Tielens F (2013) Structure of monomeric chromium(VI) oxide species
supported on silica: periodic and cluster DFT studies. J Phys Chem C 117:8138–8149
5. Gierada M, Michorczyk P, Tielens F, Handzlik J (2016) Reduction of chromia-silica catalysts:
a molecular picture. J Catal 340:122–135
6. Fong A, Yuan Y, Ivry SL, Scott SL, Peters B (2015) Computational kinetic discrimination of ethylene polymerization mechanisms for the Phillips (Cr/SiO 2 ) catalyst. ACS Catal
5:3360–3374
7. Guesmi H, Tielens F (2012) Chromium oxide species supported on silica: a representative
periodic DFT model. J Phys Chem C 116:994–1001
8. Guesmi H, Grybos R, Handzlik J, Tielens F (2014) Characterization of molybdenum
monomeric oxide species supported on hydroxylated silica: a DFT study. Phys Chem Chem
Phys 16:18253–18260
9. Guesmi H, Grybos R, Handzlik J, Tielens F (2016) Characterization of tungsten monomeric
oxide species supported on hydroxylated silica; a DFT study. RSC Adv 6:39424–39432
10. Floryan L, Borosy AP, Núñez-Zarur F, Comas-Vives A, Copéret C (2017) Strain effect and dual
initiation pathway in Cr III /SiO 2 polymerization catalysts from amorphous periodic models. J
Catal 346:50–56
11. Dapprich S, Komáromi I, Byun KS, Morokuma K, Frisch MJ (1999) A new ONIOM implementation in Gaussian98. Part I. The calculation of energies, gradients, vibrational frequencies
and electric field derivatives. J Mol Struct THEOCHEM 461–462:1–21