The influence of nanoparticles on the excitation energies of the photochromic dihydroazulene/vinylheptafulvene system

TY - JOUR

T1 - The influence of nanoparticles on the excitation energies of the photochromic dihydroazulene/vinylheptafulvene system

AU - Hillers-Bendtsen, Andreas Erbs

AU - Hansen, Mia Harring

AU - Mikkelsen, Kurt, V

PY - 2019/3/28

Y1 - 2019/3/28

N2 - This paper studies how nanoparticles affect photochromic systems, focusing on the influence of gold nanoparticles on the optical properties of the dihydroazulene/vinylheptafulvene (DHA/VHF) system. This investigation is done using a combined quantum mechanical/molecular mechanical approach treating the photochromic system quantum mechanically. The gold nanoparticle is described as gold atoms with atomic polarizabilities using molecular mechanics, thus leaving out excitations of the gold nanoparticle. The photochromic molecule is described by density functional theory using the long-range corrected functional CAM-B3LYP and the correlation consistent basis set aug-cc-pVDZ. The results show that the optical properties of the photochromic system are affected by the presence of the nanoparticle. The vinylheptafulvene molecule is especially influenced, when increasing the interaction between the molecule and the gold nanoparticle. We observe that the optical properties of the photochromic system are influenced strongly by conformational changes, relative orientation compared to the gold nanoparticle, and the molecule-cluster distance. We observe that the different molecules are affected differently by the nanoparticle. Furthermore, we suggest that experiments should be carried out to investigate how the molecules coordinate to the nanoparticle.

AB - This paper studies how nanoparticles affect photochromic systems, focusing on the influence of gold nanoparticles on the optical properties of the dihydroazulene/vinylheptafulvene (DHA/VHF) system. This investigation is done using a combined quantum mechanical/molecular mechanical approach treating the photochromic system quantum mechanically. The gold nanoparticle is described as gold atoms with atomic polarizabilities using molecular mechanics, thus leaving out excitations of the gold nanoparticle. The photochromic molecule is described by density functional theory using the long-range corrected functional CAM-B3LYP and the correlation consistent basis set aug-cc-pVDZ. The results show that the optical properties of the photochromic system are affected by the presence of the nanoparticle. The vinylheptafulvene molecule is especially influenced, when increasing the interaction between the molecule and the gold nanoparticle. We observe that the optical properties of the photochromic system are influenced strongly by conformational changes, relative orientation compared to the gold nanoparticle, and the molecule-cluster distance. We observe that the different molecules are affected differently by the nanoparticle. Furthermore, we suggest that experiments should be carried out to investigate how the molecules coordinate to the nanoparticle.

U2 - 10.1039/c8cp06539j

DO - 10.1039/c8cp06539j

M3 - Journal article

C2 - 30855612

SN - 1463-9076

VL - 21

SP - 6689

EP - 6698

JO - Physical Chemistry Chemical Physics

JF - Physical Chemistry Chemical Physics

IS - 12

ER -