Alex Brown

Alex Brown
University of Alberta | UAlberta · Department of Chemistry

PhD, University of Western Ont

About

148
Publications
9,606
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
3,157
Citations
Introduction
Alex Brown currently works at the Department of Chemistry, University of Alberta. Alex does research in Photochemistry, Spectroscopy, Main Group Chemistry, and Theoretical Chemistry.
Additional affiliations
July 2003 - present
University of Alberta
October 2002 - June 2003
Emory University
January 2002 - present
University of Alabama

Publications

Publications (148)
Article
This study aims to design a series of nonfullerene acceptors (NFAs) for photovoltaic applications having 1,4-dihydro-2,3-quinoxalinedione fused thiophene derivative as the core unit and 1,1-dicyanomethylene-3-indanone (IC) derivatives and different π-conjugated molecules other than IC as terminal acceptor units. All the investigated NFAs are found...
Preprint
Full-text available
Vibrational spectroscopy is a powerful tool for determining the local hydrogen-bonding environment. However, vibrational coupling present in H2O can make it difficult to relate vibrational spectra to a molecular description of the system. While numerous bulk studies have shed light on this phenomenon, the influence of both intra- and intermolecular...
Preprint
Full-text available
This study aims to design a series of non-fullerene acceptors (NFAs) for photovoltaic applications having 2,3-quinoxalinedione,1,4-dihydro fused thiophene derivative as the core unit and 1,1-dicyanomethylene-3-indanone (IC) derivatives and different {\pi}-conjugated molecules other than IC as terminal acceptor units. All the investigated NFAs are f...
Article
In this work, the conformer-rotamer ensemble sampling tool (CREST), with the underlying semiempirical GFN2-xtb method, was used for automated geometry exploration of the homodimers of pyrene, pyrene-4,5-dione, and pyrene-4,5,9,10-tetraone, along with the heterodimer of pyrene and pyrene-4,5,9,10-tetraone. Geometries and energies of the dimers were...
Preprint
In this work, the Conformer-Rotamer Ensemble Sampling Tool, (CREST) with the underlying semi-empirical GFN2-xtb method was used for automated geometry exploration of the homodimers of pyrene, pyrene-4,5-dione, and pyrene-4,5,9,10- tetraone, along with the heterodimer of pyrene and pyrene-4,5,9,10-tetraone. Geometries and energies of the dimers were...
Article
The intramolecular vibrational relaxation dynamics of formic acid and its deuterated isotopologues is simulated on the full-dimensional potential energy surface of Richter and Carbonnière [F. Richter and P. Carbonnière, J. Chem. Phys. 148, 064303 (2018)] using the Heidelberg MCTDH package. We focus on couplings with the torsion vibrational modes cl...
Preprint
Full-text available
The intramolecular vibrational relaxation dynamics of formic acid and its deuterated isotopologues is simulated on the full-dimensional potential energy surface of Richter and Carbonniere [F. Richter and P. Carbonniere, J. Chem. Phys., 148, 064303 (2018)] using the Heidelberg MCTDH package. Mode couplings with the torsion coordinate capturing most...
Article
Full-text available
mNeonGreen, an engineered green fluorescent protein (GFP) derived from lancelet, is one of the most brightly fluorescent homologues of Aequorea victoria jellyfish GFP (avGFP) yet reported. In this work, we investigated whether this bright fluorescence might be retained in homologs of mNeonGreen with modified chromophore structures and altered fluor...
Article
A semi-automatic sampling and fitting procedure for generating sum-of-product (Born-Oppenheimer) potential energy surfaces based on a high-dimensional model representation is presented. The adaptive sampling procedure and subsequent fitting relies on energies only and can be used for re-fitting existing analytic potential energy surfaces in sum-of-...
Preprint
In this work, the Conformer-Rotamer Ensemble Sampling Tool, (CREST) with the underlying semi-empirical GFN2-xtb method was used for automated geometry exploration of the homodimers of pyrene, pyrene-4,5-dione, and pyrene-4,5,9,10- tetraone, along with the heterodimer of pyrene and pyrene-4,5,9,10-tetraone. Geometries and energies of the dimers were...
Article
We propose a methodology to tackle the laser control of a non-stationary dark ro-vibrational state of acetylene (C 2 H 2 ), given realistic experimental limitations in the 7.7 μm (1300 cm ⁻¹ ) region. Simulations are performed using the Lindblad master equation, where the so-called Lindblad parameters are used to describe the effect of the environm...
Article
The cover image is based on the Focus Article Quantum mechanical/molecular mechanical studies of photophysical properties of fluorescent proteins by Maria Rossano‐Tapia and Alex Brown., https://doi.org/10.1002/wcms.1557.
Article
Light-responsive proteins are widely employed in bioimaging, for example, fluorescent proteins (FPs), which are comprised of a chromophore centered within a barrel-shaped protein. FPs exhibit remarkable one- and multi-photon absorption (1PA and MPA, respectively) in addition to their emissive properties. Over the last two decades, many types of qua...
Article
A series of donor–acceptor-donor (D-A-D) type small molecule (SM) donors containing Pechmann dye analogues (N, S, O) are designed and their geometrical, optoelectronic, charge transport, and photovoltaic properties are investigated using density functional theory (DFT). The structural modification of the donor backbone has been performed via additi...
Preprint
The Wittig reaction can be used for late stage functionalization of proteins and peptides to ligate glycans, pharmacophores, and many other functionalities. In this manuscript, we modified 160,000 N-terminal glyoxaldehyde peptides displayed on phage with the Wittig reaction by biotin labeled ylide under conditions that functionalize only 1% of the...
Preprint
Vacancy-ordered double perovskites Cs<sub>2</sub>SnX<sub>6</sub> (X = Cl, Br, I) have emerged as promising lead-free and ambient-stable materials for photovoltaic and optoelectronic applications. To advance these promising materials, it is crucial to determine the correlations between physical properties and their local structure and dynamics. Soli...
Article
160 000 peptides displayed on phage were subjected to the Wittig reaction with a biotinylated ylide. Deep-sequencing estimated the conversion rate for each sequence and unveiled the relationship between sequences and the rate of the Wittig reaction.
Article
In this study, density functional theory (DFT) and time dependent density functional theory (TD-DFT) are used to investigate the stabilities and spectral properties [IR, UV-vis, and two-photon absorption (2PA)] of two sets of modified RNA nucleobase tautomers. The modifications introduce either a sulfur or selenium atom to form an isothiazolo[4,3-d...
Article
Full-text available
It was previously reported that Laplace transformed local CC2 (LCC2*) provided the best agreement (MAE = 0.145 eV) when comparing vertical excitation energies to experimental λmax for a benchmark set of 17 BODIPY/Aza‐BODIPY molecules. However, these energies did not agree with values obtained from canonical CC2. Here we report LCC2* computations of...
Article
Full-text available
In this work, we present a computational investigation on the photoexcitation of indigo carmine (IC). Physical insights regarding IC photoexcitation and photolysis were obtained from a fundamental perspective through quantum chemistry computations. Density functional theory (DFT) was used to investigate the ground state while its time-dependent for...
Article
We use a phosphinoborane frustrated Lewis pair (FLP) ligand to stabilize ER2 species (E=Si, Ge; R=H or Me) for the subsequent deposition of semiconductor elements and polymers from solution. The ability to recycle the FLP phosphine‐borane ligand after element deposition is also demonstrated. Abstract The stabilization of silicon(II) and germanium(...
Article
The stabilization of silicon(II) and germanium(II) dihydrides by an intramolecular Frustrated Lewis Pair (FLP) ligand, PB, i Pr-2P(C6H4)BCy2 (Cy = cyclohexyl) is reported. The resulting hydride complexes [PB{SiH2}] and [PB{GeH2}] are indefinitely stable at room temperature, yet can deposit films of silicon and germanium, respectively, upon mild the...
Article
In this work, we present a computational investigation on diquat, paraquat, and six dipyridyl isomers (2,2′-dipyridyl, 2,3′-dipyridyl, 2,4′-dipyridyl, 3,3′-dipyridyl, 3,4′-dipyridyl, and 4,4′-dipyridyl). Ground state properties such as equilibrium structures, relative energetics, transition states for cis-trans interconversion, and vibrational freq...
Article
Electron-donating N-heterocyclic carbenes (Lewis bases, LB) and electron-accepting Lewis acids (LA) have been used in tandem to yield donor-acceptor complexes of inorganic tetrelenes LB·EH2·LA (E = Si, Ge, and Sn). Herein, we introduce the new germanium (II) dihydride adducts ImMe2·GeH2·BH3 (ImMe2 = (HCNMe)2C:) and ImiPr2Me2·GeH2·BH3 (ImiPr2Me2 = (...
Article
Full-text available
Multi-photon absorption properties, particularly two-photon absorption (2PA), of fluorescent proteins (FPs) have made them attractive tools in deep-tissue clinical imaging. Although the diversity of photophysical properties for FPs is wide, there are some caveats predominant among the existing FP variants that need to be overcome, such as low quant...
Article
The vibrational eigenenergies of the deuterated forms of formic acid (DCOOD, HCOOD, and DCOOH) have been computed using the block-improved relaxation method, as implemented in the Heidelberg multiconfiguration time-dependent Hartree package on a previously published potential energy surface [F. Richter and P. Carbonnière, J. Chem. Phys. 148, 064303...
Article
The vertical excitation energies to the S 1 and T 1 states for HFCO were determined using multi-reference (CASSCF, CASPT2, CASPT2-F12, MRCI, and MRCI-F12) and the single reference EOM-CCSD methods. The geometries, relative energies, and harmonic frequencies for the stationary points (minimum and transition state to inversion) on both the S 1 and T...
Article
Nucleobases (adenine, cytosine, guanine, and uracil), the four molecules that forms RNA, have been found to be useful in probing in the human body when modified because they can emit light. Non-modified nucleobases do not exhibit emissive properties and cannot be used as probes. Some of the modifications include the substitution of nitrogen atoms w...
Article
The nuclear quadrupole moment of aluminum (²⁷Al) has been re-evaluated by determining the electric field gradients at this nucleus for AlF and AlCl using the coupled cluster method with single, double, and perturbative triple excitations [CCSD(T)]/aug-cc-pwCVXZ (X = T and Q) accounting for both vibrational averaging and core–core/core–valence elect...
Article
In this work, we present a computational study on the antioxidant potential of myricetin 3-O-α-L-rhamnopyranoside (Compound M3) and myricetin 4′-O-α-L-rhamnopyranoside (Compound M4′). Structural parameters, bond dissociation enthalpies (BDEs), ionization potentials (IPs), proton dissociation enthalpies (PDEs), proton affinities (PAs), and electron...
Article
Application of fluorescent proteins (FPs), e.g., as probes for biological imaging, has led to the goal of finding FPs with notable one- and two-photon absorption, OPA and TPA, respectively, features. The variables that affect the TPA cross-section are many, e.g., structurally speaking, some studies have shown its magnitude is influenced by the pres...
Article
The organotin precursors 6‐Br‐Ace‐5‐SnBu3 (6, Ace = acenaphthyl) and 6‐Ph2E‐Ace‐5‐SnBu3 (7a: E = P; 7b: E = As; 7c: E = Sb) were prepared and used for the synthesis of organogold complexes, namely, the homodinuclear arylgold(I) species (6‐Ph2E‐Ace‐5‐Au)2 (8a: E = P; 8b: E = As; 8c: E = Sb), arylgold(III) dichloride 6‐Ph2P‐Ace‐5‐AuCl2 (9), diarylgol...
Article
The synthesis of the first bismuth‐containing macromolecules that exhibit phosphorescence in the solid state and in the presence of oxygen is reported. These red emissive high molecular weight polymers (> 300 kDa) feature benzobismoles appended to a hydrocarbon scaffold, and were built via an efficient ring‐opening metathesis (ROMP) protocol. Moreo...
Article
The synthesis of the first bismuth‐containing macromolecules that exhibit phosphorescence in the solid state and in the presence of oxygen is reported. These red emissive high molecular weight polymers (> 300 kDa) feature benzobismoles appended to a hydrocarbon scaffold, and were built via an efficient ring‐opening metathesis (ROMP) protocol. Moreo...
Article
Non-invasive molecular imaging techniques are accruing more interest in the last decades. Several radiolabelling elements have been FDA-approved and are currently used to characterize tumors. In this study, the DNA intercalating agent doxorubicin was radiolabelled with ¹²⁵I. Several parameters for the radiolabelling reaction were investigated and o...
Article
Full-text available
In this work, we present a computational study on the antioxidant potential of myricetin 3,4\(^{\prime }\)-di-O-α-L-rhamnopyranoside (Compound M). A density functional theory (DFT) approach with the B3LYP and LC-ωPBE functionals and with both the 6-311G(d,p) and 6-311+G(d,p) basis sets was used. The focus of the investigation was on the structural...
Article
Molecular dynamic (MD) simulations were carried out to obtain the conformational changes of the chromophore in the gold fluorescent protein (PDB ID: 1OXF). To obtain two-photon absorption (TPA) cross-sections, time dependent density functional theory (TD-DFT) computations were performed for chromophore geometries sampled along the trajectory. The T...
Article
The structures and energetics of two dihydrochalcones (phloretin and its glycoside phlorizin) were examined with density functional theory, using the B3LYP, M06-2X, and LC-ω PBE functionals with both the 6-311G(d,p) and 6-311 + G(d,p) basis sets. Properties connected to antioxidant activity, i.e., bond dissociation enthalpies (BDEs) for OH groups a...
Article
Full-text available
A well-defined Ir-allyl complex catalyzes the Z-selective cross-coupling of allyl carbonates with α-aryl diazo esters. The process overrides the large thermodynamic preference for E-products typically observed in metal-mediated coupling reactions to enable the synthesis of Z,E-dieneoates in good yield with selectivities consistently approaching or...
Article
Previous research in our group showed that tellurophenes with pinacolboronate (BPin) units at the 2- and/or 5-positions displayed efficient phosphorescence in the solid state, both in the presence of oxygen and water. In this current study, we show that lumi-nescence from a tellurophene is possible when various aryl-based substituents are present,...
Article
The minimum energy structures, i.e., trans-HONO, cis-HONO, HNO2, and OH + NO, as well as the corresponding transition states, i.e., TStrans↔cis, TS1,2H−shift, and TS1,3H−shift, on the ground state potential energy surface (PES) of HONO have been characterized at the CCSD(T)-F12/cc-pVTZ- F12 level of theory. Using the same level of theory, a six-dim...
Article
In this paper, the use of the neural network (NN) method with exponential neurons for directly fitting ab initio data to generate potential energy surfaces (PESs) in sum-of-product form will be discussed. The utility of the approach will be highlighted using fits of CS2, HFCO, and HONO ground state PESs based upon high-level ab initio data. Using a...
Article
Front Cover: The morphological, crystalline, and optoelectronic responses of the polymer PBST3HT, a novel triple-chalcogenophene polymer, enable control of the crystalline structure and optical bandgap. Thermal annealing assists shifts between polymer phases, tuning the bandgap and involving a color change of the homogeneous polymer films. Further...
Article
The authors study adjustable bandgap properties of the novel triple chalcogenophene-based polymer poly-(3-hexyl-2(3-(4-hexylthiophene-2-yl)-4,5-butylselenophene-1-yl)-5-(4,5-butyltellurophene-1-yl)thiophene) through a combination of morphological, spectroscopic, and computational techniques. The bandgap can be tuned after polymerization by means of...
Chapter
Two-photon absorption (TPA) leads to higher-energy excited electronic states via the simultaneous absorption of two photons. In TPA, the absorption is directly proportional to the square of incident light intensity, and thus lasers are required for excitation. The advantages of TPA microscopy include better focus and less out-of-focus bleaching, to...
Article
The effects of explicit hydrogen bonding with H2O on the resonance Raman spectra of uracil and thymine are examined computationally. The three bonding sites in uracil and thymine that form the lowest energy uracil-H2O and thymine-H2O complexes, as well as a more limited number of low-lying ones containing two waters, are considered. The ground stat...
Article
In this article our attempts to tune the color of luminescence within a new class of aggregation-induced emission (AIE) active tellurophenes is reported along with computational details that include spin-orbit coupling effects so as to better understand the nature of emission in the phosphorescent tellurophene (B-Te-6-B). Despite not meeting some o...
Article
The tetrameric red fluorescent protein from Discosoma sp. coral (DsRed) has previously been engineered to produce dimeric and monomeric fluorescent variants with excitation and emission profiles that span the visible spectrum. The brightest of the effectively monomeric DsRed variants is tdTomato - a tandem fusion of a dimeric DsRed variant. Here we...
Article
Two-photon spectroscopy of fluorescent proteins is a powerful bio-imaging tool known for deep tissue penetration and little cellular damage. Being less sensitive than the one-photon microscopy alternatives, a protein with a large two-photon absorption (TPA) cross-section is needed. Here, we use time-dependent density functional theory (TD-DFT) at t...
Article
Full-text available
The HBrO2 isomers have been analyzed computationally to confirm the previous experimental assignments for HOOBr and HOBrO and to assist in future identification of the as yet unobserved HBr(O)O isomer. Optimized geometries of the HOOBr, HOBrO, and HBr(O)O isomers and the transition states connecting them were obtained at the CCSD(T)/O, H: aug-cc-pV...
Article
We have constructed a (semi)-global six-dimensional potential energy surface (PES) for HFCO, incorporating the equilibrium, cis- and trans-isomers (HOCF) as well as the transition states connecting them. The PES is based on a fit to 15000 CCSD(T)-F12/cc-pVTZ-F12 ab initio energies. The sum-of-products PES, obtained using neural network exponential...
Article
A six-dimensional potential energy surface (PES) for formyl fluoride (HFCO) is fit in a sum-of-products form using neural network exponential fitting functions. The ab initio data upon which the fit is based were computed at the explicitly correlated coupled cluster with single, double, and perturbative triple excitations [CCSD(T)-F12]/cc-pVTZ-F12...
Article
We present a computational study on two flavonols that were recently isolated from Loranthaceae family plant extracts: kaempferol 3-O-α-L-arabinofuranosyl-(1 → 3)-α-L-rhamnoside and quercetin 3-O-α-L-arabinofuranosyl-(1 → 3)-α-L-rhamnoside. Their structures and energetics have been investigated at the density functional level of theory, up to B3LYP...
Article
A series of 11 different BODIPY dimers is carefully examined by means of ab initio and TDA-DFT methods. Vertical and 0--0 excitation energies along with the tetra-radical character of these dimers are determined. Possible application of a series of linked dimers for photodynamic therapy (PDT) was investigated through computing their excitation ener...
Chapter
Two-photon absorption (TPA) leads to higher-energy excited electronic states via the simultaneous absorption of two photons. In TPA, the absorption is directly proportional to the square of incident light intensity, and thus lasers are required for excitation. The advantages of TPA microscopy include better focus and less out-of-focus bleaching, to...
Data
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and...
Data
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and...
Data
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and...
Article
Full-text available
Two-photon spectroscopy of fluorescent proteins is a powerful bio-imaging tool characterized by deep tissue penetration and little damage. However, two-photon spectroscopy has lower sensitivity than one-photon microscopy alternatives and hence a protein with a large two-photon absorption cross-section is needed. We use time-dependent density functi...
Article
The stability of a variety of linear and cyclic (BN)n (n = 1–3) adducts with N-heterocyclic carbene (ImMe2; ImMe2 = [(HCNMe)2C:]), N-heterocyclic olefin (ImMe2CH2) and Wittig (Me3PCH2) donors has been examined using M05-2X/cc-pVTZ computations. The strength and nature of the bonds have been investigated using natural bond orbital (NBO) and atoms-in...
Article
The vertical excitation energies of 17 boron–dipyrromethene (BODIPY) core structures with a variety of substituents and ring sizes are benchmarked using time-dependent density functional theory (TD-DFT) with nine different functionals combined with the cc-pVTZ basis set. When compared to experimental measurements, all functionals provide mean absol...
Article
The resonance Raman spectra of the 5-halogenated (F, Cl, and Br) uracils are simulated via the Herzberg-Teller (HT) short-time dynamics formalism. The gradient of the S1 excited state is computed at the CAMB3LYP/aug-cc-pVTZ level of theory in the conductor-like Polarizable Continuum Model for water (C-PCM, H2O), based on the equilibrium geometry de...
Article
We present a computational study on HIO2 molecules. Ground state properties such as equilibrium structures, relative energetics, vibrational frequencies, and infrared intensities were obtained for all the isomers at the coupled-cluster with single and double excitations as well as perturbative inclusion of triples (CCSD(T)) level of theory with the...
Chapter
A brief introduction to quantum computing is provided and the potential use of molecules as the platform is discussed. The basic building blocks (quantum bits, quantum gates, and quantum algorithms) are described in order to emphasize the requirements for realizing a quantum computer, and, the advantages quantum computation has over its classical c...
Article
The zirconium-mediated syntheses of pinacolboronate (BPin) appended benzo[b]tellurophenes and two phenyl/BPin substituted tellurophene isomers with different colors of emission have been achieved. These species are new additions to an emerging class of inorganic heterocycles that display visible phosphorescence in the solid state under ambient cond...
Article
We present isolable examples of formal zinc hydride cations supported by N-heterocyclic carbene (NHC) donors, and investigate the dual electrophilic and nucleophilic (hydridic) character of the encapsulated [ZnH]+ units by computational methods and preliminary hydrosilylation catalysis. A positive approach: Isolable examples of formal zinc hydride...
Article
Two-photon spectroscopy of fluorescent proteins is a powerful bioimaging tool. Considerable effort has been made to measure absolute two-photon absorption (TPA) for the available fluorescent proteins. Being a technically involved procedure, there is significant variation in the published experimental measurements even for the same protein. In this...
Article
The resonance Raman spectrum of uracil is simulated using the Herzberg-Teller short-time dynamics formalism. The ground state geometry is optimized at the levels of PBE0/aug-cc-pVTZ and B3LYP/aug-cc-pVTZ, respectively. The gradient of the bright excited state is computed using Time Dependent Density Functional Theory (TD-DFT) and Spin Flip Time Dep...
Article
The synthesis of the first examples of tellurophenes exhibiting phosphorescence in the solid state and under ambient conditions (room temperature and in air) is reported. Each of these main-group-element-based emitters feature pinacolboronates (BPin) as ring-appended side groups. The nature of the luminescence observed was also investigated using c...
Chapter
Lasers are created to study the timescale of electron motion in atoms and molecules. They also have wide applications in areas like solid state, plasma physics, nanoscience and defence technology. This book helps readers to master the large variety of physical phenomena and technological aspects involved in laser technology. Besides explaining the...
Article
The stability of a variety of borane (BH3 and BH2NHMe) and silane (SiHnPh4–n, n = 0–4) adducts with diamino (NHC) and aminoalkyl (CAAC) carbenes has been carefully examined using M06-2X/cc-pVDZ computations, including natural bond orbital and atoms-in-molecules analyses. Moreover a potential mechanism for the hydride-mediated ring expansion of the...
Article
The nuclear quadrupole coupling and spin-rotation constants of aluminum in AlH and AlD have been determined using coupled cluster theory with single and double excitations as well as perturbative inclusion of triples [CCSD(T)] combined with large correlation-consistent basis sets, cc-pCVXZ (X = T, Q and 5) and aug-cc-pCVXZ (X = T, Q). The anharmoni...
Article
To branch or not to branch: A mild stepwise route to various linear and branched (GeCl2 )x oligogermylenes supported by Lewis bases is reported, including the carbene-bound Ge4 complex NHC⋅GeCl2 Ge(GeCl3 )2 . Dipp=2,6-iPr2 C6 H3 , NHC=N-heterocyclic carbene.
Article
The elusive parent inorganic ethylene H2GeGeH2 has been isolated in the form of a stable complex for the first time via donor–acceptor coordination with suitable Lewis base/acid combinations (LB·H2Ge-GeH2·LA; LB = N-heterocyclic carbene or N-heterocyclic olefin; LA = W(CO)5). The nature of the bonding in these species was investigated by density fu...
Article
In this work, we present time dependent density functional theory (TD-DFT) computations of the photophysical properties for a recently synthesized family of emissive RNA nucleobases (see: D. Shin, R.W. Sinkeldam, Y. Tor, Journal of the American Chemical Society 133 (2011) 14912–14915). These modified analogues are obtained by replacing the imidazol...
Article
The ground state potential energy and dipole moment surfaces for CS$_{2}$ have been determined at the CASPT2/C:cc-pVTZ, S:aug-cc-pV(T+d)Z level of theory. The potential energy surface has been fit to a sum-of-products form using the neural network method with exponential neurons. A generic interface between neural network potential energy surface f...