TY  - JOUR
A1  - Boese, Adrian Daniel
T1  - Density Functional Theory and Hydrogen Bonds: Are We There Yet?
JF  - ChemPhysChem : a European journal of chemical physics and physical chemistry
N2  - Density functional theory (DFT) has become more successful at introducing dispersion interactions, and can be thus applied to a wide range of systems. Amongst these are systems that contain hydrogen bonds, which are extremely important for the biological regime. Here, the description of hydrogen-bonded interactions by DFT with and without dispersion corrections is investigated. For small complexes, for which electrostatics are the determining factor in the intermolecular interactions, the inclusion of dispersion with most functionals yields large errors. Only for larger systems, in which van der Waals interactions are more important, do dispersion corrections improve the performance of DFT for hydrogen-bonded systems. None of the studied functionals, including double hybrid functionals (with the exception of DSD-PBEP86 without dispersion corrections), are more accurate than MP2 for the investigated species.
KW  - ab initio calculations
KW  - basis sets
KW  - density functional calculations
KW  - hydrogen bonds
KW  - intermolecular interactions
Y1  - 2015
U6  - https://doi.org/10.1002/cphc.201402786
SN  - 1439-4235
SN  - 1439-7641
VL  - 16
IS  - 5
SP  - 978
EP  - 985
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Klaper, Matthias
A1  - Linker, Torsten
T1  - New Singlet Oxygen Donors Based on Naphthalenes: Synthesis, Physical Chemical Data, and Improved Stability
JF  - Chemistry - a European journal
N2  - Singlet oxygen donors are of current interest for medical applications, but suffer from a short half-life leading to low singlet oxygen yields and problems with storage. We have synthesized more than 25new singlet oxygen donors based on differently substituted naphthalenes in only a few steps. The influence of functional groups on the reaction rate of the photooxygenations, thermolysis, half-life, and singlet oxygen yield has been thoroughly studied. We determined various thermodynamic data and compared them with density functional calculations. Interestingly, remarkable stabilities of functional groups during the photooxygenations and stabilizing effects for some endoperoxides during the thermolysis have been found. Furthermore, we give evidence for a partly concerted and partly stepwise thermolysis mechanism leading to singlet and triplet oxygen, respectively. Our results might be interesting for dark oxygenations and future applications in medicine.
KW  - density functional calculations
KW  - oxygenation
KW  - peroxides
KW  - photodynamic therapy
KW  - singlet oxygen
Y1  - 2015
U6  - https://doi.org/10.1002/chem.201500146
SN  - 0947-6539
SN  - 1521-3765
VL  - 21
IS  - 23
SP  - 8569
EP  - 8577
PB  - Wiley-VCH
CY  - Weinheim
ER  -