Understanding the Two-Photon Absorption Spectrum of PE2 Platinum Acetylide Complex

Autor(es)

Vivas, Marcelo G. ^{[1, 2]} ; De Boni, Leonardo ^[1] ; Cooper, Thomas M. ^[3] ; Mendonca, Cleber R. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Fis Sao Carlos, Grp Foton, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Fed Alfenas, Inst Ciencia Tecnol, BR-37715400 Pocos De Caldas, MG - Brazil

^[3] Air Force Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 - USA

• Tipo de documento: Artigo Científico
• Fonte: Journal of Physical Chemistry A; v. 118, n. 30, p. 5608-5613, JUL 31 2014.
• Citações Web of Science: 9

Resumo

Herein, we report on the two-absorption cross-section spectrum of trans-Pt(PBu3)(2) (C equivalent to C-C6H4-C equivalent to C-C6H5)(2) (PE2) platinum acetylide complex employing the femtosecond wavelength-tunable Z-scan technique. The PE2 complex can be visualized as two branches containing two phenylacetylene units, each one linked by a platinum center, completely transparent in the visible region. Because of this structure, large delocalization of pi-electrons allied to the strong intramolecular interaction between the branches is expected. The 2PA absorption spectrum was measured using the femtosecond wavelength-tunable Z-scan technique with low repetition rate (1 kHz), in order to obtain the 2PA spectrum without excited-state contributions. Our results reveal that PE2 in dichloromethane solution presents two 2PA allowed bands located at 570 and 710 nm, with cross section of about 320 and 45 GM, respectively. The first one is related to the strong intramolecular interaction between the molecule's branches due to the presence of platinum atom, while the second one is associated with the breaking of symmetry of the chromophore in solution due, most probably to a large twisting angle of the ligand's phenyl rings relative to the Pt core. (AU)

• Processo FAPESP: 11/12399-0 - Aplicações de pulsos de femtossegundos em óptica não linear: espectroscopia, formatação de pulsos e microfabricação
• Beneficiário: Cleber Renato Mendonça
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 11/06489-6 - Efeitos do estado de polarização de pulsos ultracurtos sobre a absorção de dois fótons em compostos orgânicos
• Beneficiário: Marcelo Gonçalves Vivas
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado