Premium
Theoretical analysis of aggregation in block‐copolymer films: The optical signature
Author(s) -
Giro Ronaldo,
Davila Liliana Y. A.,
Machado Angelita M.,
Caldas Marilia J.,
Akcelrud Leni
Publication year - 2009
Publication title -
international journal of quantum chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.484
H-Index - 105
eISSN - 1097-461X
pISSN - 0020-7608
DOI - 10.1002/qua.21979
Subject(s) - stacking , delocalized electron , copolymer , stack (abstract data type) , electron delocalization , phenanthrene , block (permutation group theory) , zindo , chemistry , absorption (acoustics) , chemical physics , materials science , polymer , molecule , computer science , organic chemistry , geometry , mathematics , composite material , programming language
We focus this work on the theoretical investigation of the block‐copolymer poly[oxyoctyleneoxy‐(2,6‐dimethoxy‐1,4phenylene‐1,2‐ethinylene‐phenanthrene‐2,4diyl) named as LaPPS19, recently proposed for optoelectronic applications. We used for that a variety of methods, from molecular mechanics to quantum semiempirical techniques (AM1, ZINDO/S‐CIS). Our results show that as expected isolated LaPPS19 chains present relevant electron localization over the phenanthrene group. We found, however, that LaPPS19 could assemble in a π‐stacked form, leading to impressive interchain interaction; the stacking induces electronic delocalization between neighbor chains and introduces new states below the phenanthrene‐related absorption; these results allowed us to associate the red‐shift of the absorption edge, seen in the experimental results, to spontaneous π‐stack aggregation of the chains. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010