Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-24T18:49:04.385Z Has data issue: false hasContentIssue false

Preferential photostructural modification of heteroleptic titanium alkoxides for molecular assembly

Published online by Cambridge University Press:  31 January 2011

J.D. Musgraves*
Affiliation:
Materials Science and Engineering Department, University of Arizona, Tucson, Arizona 85721
B.G. Potter Jr.
Affiliation:
Materials Science and Engineering Department, University of Arizona, Tucson, Arizona 85721
Robin M. Sewell
Affiliation:
Sandia National Laboratories, Advanced Materials Laboratory, Albuquerque, New Mexico 87106
Timothy J. Boyle
Affiliation:
Sandia National Laboratories, Advanced Materials Laboratory, Albuquerque, New Mexico 87106
*
a)Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

The response of a mononuclear, heteroleptic titanium alkoxide [(OPy)2Ti(4MP)2, where OPy = pyridinecarbinol; NC5H4(CH2O) and 4MP = 4-mercaptophenol; OC6H4(SH)] to ultraviolet (UV) irradiation in dilute solution and in solid-state samples has been measured. Vibrational spectroscopy [Fourier transform infrared (FTIR) absorption and Raman scattering] was used to monitor changes in molecular structure upon exposure to 337.1- and 365-nm light. Assignment of spectral features to vibrational modes of the molecule was aided by a normal-mode analysis of the energy-minimized molecular structure within a density-functional theory framework. Photoinduced decreases in peak areas were observed in both FTIR spectra of the precursor solutions and Raman data collected from solution-cast films of the precursor material. These changes were associated with vibrational modes localized at the 4MP ligands. Conversely, no significant modification of vibrational structure associated with the OPy moiety was observed under the excitation conditions examined. In a related study, thin films of the precursor were cast, sampled, and irradiated with UV light in scintillation vials under hydrated air (40% relative humidity) and dry Ar to evaluate the influence of local atmospheric composition on the photoresponse. An increase in the magnitude of photoinduced vibrational changes was observed in the moist-air environment, again associated primarily with the 4MP ligand. The results support an interpretation of these structural changes in terms of a preferential enhancement of hydrolysis at the 4MP site under these conditions. These findings are discussed in the context of an optically driven molecular assembly strategy based on the photoinitiation of intermolecular bonding at selected sites about the metal center.

Type
Articles
Copyright
Copyright © Materials Research Society2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1Boyle, T.J., Pedrotty, D.M., Alam, T.M., Vick, S.C.Rodriguez, M.A.: Structural diversity in solvated lithium aryloxides. Syntheses, characterization, and structures of [Li(OAr) (THF)(x)](n) and [Li(OAr)(py)(x)](2) complexes where Oar = OC6H5, OC6H4(2-Me), OC6H3(2,6-(Me))(2), OC6H4(2-Pr-i), OC6H3(2,6-(Pr-i))(2), OC6H4(2- Bu-t), OC6H3(2,6-(Bu-t))(2). Inorg. Chem. 39, 5133 2000CrossRefGoogle Scholar
2Boyle, T.J., Zechmann, C.A., Alam, T.M.Rodriguez, M.A.: From clusters to ionic complexes: Structurally characterized thallium titanium double alkoxides. Inorg. Chem. 41, 946 2002CrossRefGoogle ScholarPubMed
3Boyle, T.J., Segall, J.M., Alam, T.M., Rodriguez, M.A.Santana, J.M.: Chemistry of a novel family of tridentate alkoxy tin(II) clusters. J. Am. Chem. Soc. 124, 6904 2002CrossRefGoogle ScholarPubMed
4Dhoshi, D., Huesing, N.K., Lu, M., Fan, H., Simmons-Potter, K., Potter, B.G. Jr., Hurd, A.J.Brinker, C.J.: Optically, defined multifunctional patterning of photosensitive thin-film silica mesophases. Science 290, 107 2000CrossRefGoogle Scholar
5Segawa, H., Tateishi, K., Arai, Y., Yoshida, K.Kaji, H.: Patterning of hybrid titania film using photopolymerization. Thin Solid Films 466, 48 2004CrossRefGoogle Scholar
6Ohya, T., Nakayama, A., Ban, T., Ohya, Y.Takahashi, Y.: Effect of photoirradiation on the properties of layered titanate thin films from transparent aqueous titanate sols. Bull. Chem. Soc. Jpn. 76, 429 2003CrossRefGoogle Scholar
7Asakuma, N., Hirashima, H., Imai, H., Fukui, T., Maruta, A., Toki, M.Awazu, K.: Photocrystallization of amorphous ZnO. J. Appl. Phys. 92, 5705 2002CrossRefGoogle Scholar
8Kim, H-R., Park, O-H., Choi, Y-K.Bae, B-S.: Photobleaching of gamma- glycidoxypropyltrimethoxysilane-chelated metal alkoxide gel films. J. Sol.-Gel Sci. Technol. 19, 607 2000CrossRefGoogle Scholar
9Segawa, H., Adachi, S., Arai, Y.Yoshida, K.: Fine patterning of hybrid titania films by ultraviolet irradiation. J. Am. Ceram. Soc. 86, 761 2003CrossRefGoogle Scholar
10Boyle, T.J., Sewell, R.M., Ottley, L.A.M., Pratt, H.D., Quintana, C.J.Bunge, S.D.: Controlled synthesis of a structurally characterized family of sterically constrained heterocyclic alkoxy-modified titanium alkoxides. Inorg. Chem. 46, 1825 2007CrossRefGoogle ScholarPubMed
11Imao, T., Hazama, D., Noma, N.Ito, S.: Photopatterning of titanium oxide gel films prepared from titanium alkoxide modified with hydroxyl-substituted aromatic ketones. J. Ceram. Soc. Jpn. 114, 238 2006CrossRefGoogle Scholar
12Rajh, T., Chen, L.X., Lukas, K., Liu, T., Thurnauer, M.C.Tiede, D.M.: Surface restructuring of nanoparticles: An efficient route for ligand-metal oxide crosstalk. J. Phys. Chem. B. 106, 10543 2002CrossRefGoogle Scholar
13Kim, H.M., Miyaji, F., Kokubo, T.Nakamura, T.: Effect of heat treatment on apatite-forming ability of Ti metal induced by alkali treatment. J. Mater. Sci.: Mater. Med. 8, 341 1997Google ScholarPubMed
14Téllez, L., Rubio, J., Rubio, F., Morales, E.Oteo, J.L.: FT-IR study of the hydrolysis and polymerization of tetraethyl orthosilicate and polydimethyl siloxane in the presence of tetrabutyl orthotitanate. Spectrosc. Lett. 37, 11 2004CrossRefGoogle Scholar