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MP22

Code: MP22	Time Slot/Poster Number: 083	Session: Resonance Raman in Biological and Chemical systems
Initial Excited-state Structural Dynamics of 9-Methyladenine
Sulayman Oladepo; Glen Loppnow
University of Alberta, Edmonton, Canada

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Summary
Nucleobases are the UV chromophores in DNA. Therefore, it is their photophysics and photochemistry that govern the photostability of DNA. UV resonance Raman (UVRR) spectroscopy is a sensitive probe of excited-state structure and dynamics. Therefore, we have UVRR spectroscopy to probe the initial excited-state structural dynamics of 9-methyladenine (9-MeA). Self-consistent analysis of the resulting resonance Raman excitation profiles and the absorption spectrum revealed a relatively photostable molecule, compared to pyrimidines. We also found that about 66% of the total reorganization energy of 9-MeA lie along photochemically relevant modes. These results are discussed in the context of photostability and photochemistry.

Code: MP22	Time Slot/Poster Number: 084	Session: Resonance Raman in Biological and Chemical systems
Correlations between Ligand Binding Properties and Redox States of Haem and Disulphide Bond in Neuroglobin.
Leila Hafsi; Hirofumi Tsujino; Taku Yamashita; Hiroshi Aoyama; Tadayuki Uno
Graduate School of Pharm. Sci. Osaka University, Suita, Japan

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Summary
Neuroglobin (Ngb) expressed predominantly in the brain and nerve system is a new member of the vertebrate globin family. The solved structure showed that Ngb contains a hexa-coordinated haem iron, which allows exogenous ligand binding. In addition, Ngb has three cysteine (Cys) residues, and two of them form an intramolecular disulphide bond. Since the redox states of haem iron and the disulphide bond have been supposed to be important for the physiological functions of Ngb, we measured affinities for exogenous ligands and resonance Raman spectra in the ferric and ferrous states focusing on the redox states of the disulphide bond.

Code: MP22	Time Slot/Poster Number: 085	Session: Resonance Raman in Biological and Chemical systems
Disentangling Interactions of an Azole Antibiotic with a Flavohemoglobin from S. aureus
Smilja Todorovic¹; Lígia Nobre¹; Ana Filipa Tavares¹; Peter Hildebrandt²; Miguel Teixeira¹; Lígia Saraiva ¹
¹ITQB, New University of Lisbon, Oeiras, Portugal; ²Technische Universitat Berlin Institut fur Chemie, Berlin, Germany

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Summary
Flavohemoglobins (Hmps) became attractive targets for antibiotic development due to the fact that they are capable of protecting pathogenic bacteria from human immune system. We used RR spectroscopy in order to address the interaction of the S. aureus Hmp with an azole antibiotic, miconiazole. Based on careful analysis of the RR spectra of Hmp and Hmp / antibiotic, structural changes on the level of heme pocket, induced by miconazole, were revealed. Taken together with other spectroscopic results and viability tests (wild-type vs. Δhmp cells), RR data helped us establish that antiobiotic/Hmp interaction contributes to the azole susceptibility of S. aureus.

Code: MP22	Time Slot/Poster Number: 086	Session: Resonance Raman in Biological and Chemical systems
Hydrophobic Residues Regulate Distal Histidine Coordinations in Human Cgb and Ngb
Hirofumi Tsujino¹; Taku Yamashita¹; Leila Hafsi¹; Azusa Nose¹; Kaori Kukino¹; Katsutoshi Yoshizato²; Norifumi Kawada²; Yoshitsugu Shiro³; Hiroshi Aoyama¹; Tadayuki Uno¹
¹Graduate School of Pharm. Sci., Osaka Univ., Suita, Japan; ²Graduate School of Medicine, Osaka City Univ., Osaka, Japan; ³RIKEN Harima Institute/SPring-8, Hyogo, Japan

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Summary
Neuroglobin (Ngb) and Cytoglobin (Cgb) are new members of the vertebrate globin family. The solved structures of Ngb and Cgb indicated that both of them contain hexa-coordinated heme, and the coordination of one of the ligands, distal histidine, could be regulated by the nearby residues. Here, we focused on hydrophobic residues, which shape the heme pocket and are close to the distal histidine. We prepared mutants of these residues, and investigated ligand binding properties with UV-vis and resonance Raman spectroscopic methods. The results suggested that orientation of distal histidine is perturbed by the mutation of these hydrophobic residues.

Code: MP22	Time Slot/Poster Number: 087	Session: Resonance Raman in Biological and Chemical systems
Vibrational Spectroscopy Study of the Interaction of Quinoline Antimalarials with Ferriprotoporphyrin IX
Mehdi Asghari Khiavi
McGill University, Montreal, Canada

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Summary
The first vibrational spectroscopy evidence is presented in the favor of formation of a salt bridge between the tertiary amino nitrogen of 4-aminoquinolines and a propionate group of heme. IR spectroscopy data show that ferriprotoporphyrin IX does not form a complex with chloroquine and rules out the hypothesis that chloroquine binds to ferriprotoporphyrin IX μ-oxo dimer with a stoichiometry of 1 chloroquine : 2 μ-oxo dimers. When compared with 4-aminoquinolines (chloroquine and quinacrine), arylmethanol antimalarials (quinine and mefloquine) have a different mechanism of interaction, namely through coordination of the Fe(III) centre of the porphyrin to the 9-hydroxyl group of the drug.

Code: MP22	Time Slot/Poster Number: 088	Session: Resonance Raman in Biological and Chemical systems
Resonance Raman Spectroscopy of an Iron Complex Containing a Phenanthrolinic Extended Tetraaza Proligand: Fe(dpq-qx)3
Norberto Goncalves¹; Renata Sancassani¹; Felipe Assad¹; Fabio Miranda²
¹Universidade Federal de São Paulo, Diadema, Brazil; ²Universidade Federal Fluminense, Niterói, Brazil

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Summary
Complexes containing alpha,alpha'–diimines extended ligands are of current interest in the literature. The iron(II) complex Fe(dpq-qx)3 containing the ligand dipyrido[3,2-f:20,30-h]quinoxalino[2,3-b]quinoxaline (dpq-qx) was studied by resonance Raman spectroscopy, to get information about the electronic transistions. It was observed two groups of intensified modes, one at ca. 500 nm and another at ca. 400 nm, probably related, respectively, to the MLCT transition and to the intraligand transistion, as indicated by the nature of the intensified modes.

Code: MP22	Time Slot/Poster Number: 089	Session: Resonance Raman in Biological and Chemical systems
Self-association and Hydrogen Bonding of Propionaldehyde in Binary Mixtures with Water and Methanol:A Concentration dependent Raman and DFT Study
Sunil Kumar Srivastava¹; Dheeraj Kumar Singh¹; Sebastian Schlücker²; B. P. Asthana¹
¹Department of Physics, Varanasi, India; ²Fachbereich Physik, Universität Osnabrück, Osnabrück, Germany

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Summary
The Raman spectra of neat propionaldehyde (propanal) and its binary mixtures with hydrogen donor solvents, water and methanol with different mole fractions of propanal were recorded in the nu(C=O) stretching region, 1600-1800 cm-1. Raman peaks corresponding to self-associated and hydrogen bonded species were identified and the peak at ~ 1721 cm-1 was attributed to the self-associated species, which was confirmed further by measuring the Raman spectra of propanal in a non-polar solvent, n-heptane at high dilution (C = 0.05), where the intensity of this band diminishes considerably.

Code: MP22	Time Slot/Poster Number: 090	Session: Resonance Raman in Biological and Chemical systems
Short-time Photodecay dynamics of meso-Tetra(p-hydroxyphenyl)porphine in the Condensed Phase explored via Resonance Raman Spectroscopy and Density Functional Theory Calculation
Huigang Wang
Hangzhou, China

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Summary
Resonance Raman spectra of meso-Tetra(p-hydroxyphenyl)porphine (THPP) were obtained with 397.9, 416 and 514 nm excitation wavelengths. The RRs indicate that the Franck-Condon region photo relaxation dynamics for S0→S5 transition is predominantly along the totally symmetric Cm-phC stretching and the CβCβ stretch and simultaneously along the asymmetric (CmCa)as stretch、V(phC=C)as stretch vibrational processes while that for S0→S4 transition is predominantly along the Cm-phC stretching and pyrrole breathing. The excited state structural dynamics of THPP shows that By→Bx electronic relaxation occurs in tens of femto-seconds and the short-time dynamics were interpreted with account of the time-dependent wave packet theory and Herzberg-Teller contributions.

Code: MP22	Time Slot/Poster Number: 091	Session: Resonance Raman in Biological and Chemical systems
UV Resonance Raman Spectroscopy of Ethylguanidine
Jonathan Wert; Sanford Asher
University of Pittsburgh, Pittsburgh, PA

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Summary
Due to its high selectivity and sensitivity and good temporal resolution, UV resonance Raman (UVRR) spectroscopy has been applied to the study of protein and peptide structure and folding dynamics. Most studies focus on the backbone structure, while there is relatively less known about the behavior of the sidechains. In this study, we examined the arginine sidechain and the effect of environment on the UVRR spectra of ethylguanidine. The spectra for each compound were measured in both acetonitrile and water.

Code: MP22	Time Slot/Poster Number: 092	Session: Resonance Raman in Biological and Chemical systems
UV Resonance Raman Study of TTR(105-115) Structural Evolution as a Function of Temperature
Sophia Hayes; Galatia Pieridou; Christiana Avgousti-Menelaou; Phanourios Tamamis; George Archontis
University of Cyprus, Nicosia, Cyprus

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Summary
UVRR spectroscopy was used to probe the temperature dependence of the TTR(105-115) peptide conformation in dilute solution. This peptide fragment has been shown to form ordered amyloid fibrils in vitro, constituting it an ideal model for the study of fibrillization in general. This study resulted in significant insights regarding the conformational response of this peptide to a changing environment, probing both changes in the Tyr local environment and changes in the secondary structure. The experimental findings are supported by explicit-solvent replica-exchange MD simulations.

Code: MP22	Time Slot/Poster Number: 093	Session: Resonance Raman in Biological and Chemical systems
Deep Ultraviolet Resonance Raman Spectroscopy of Explosives
David Tuschel¹; Aleksandr Mikhonin¹; Brian Lemoff²; Sanford Asher¹
¹University of Pittsburgh, Pittsburgh, PA; ²West Virginia High Technology Foundation, Fairmont, WV

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Summary
We have determined deep ultraviolet (229 nm) Raman cross-sections of several explosives such as trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), cyclotrimethylene-trinitramine (RDX), the chemically related nitroamine explosive HMX, and ammonium nitrate. In addition to pure explosives, we have studied complex explosive mixtures that are commercially available. One such material is the plastic explosive Semtex, the primary components of which are PETN and RDX.

Code: MP22	Time Slot/Poster Number: 094	Session: Resonance Raman in Biological and Chemical systems
Raman-assisted X-ray Biocrystallography
Alessandro Vergara
University of Naples "Federico II", Naples, ITALY

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Summary
Raman microscopy is having increasing applications into molecular biology, ranging from studies on primary structure features [1], secondary structure analysis [2], ligand binding [3] and protein reactivity. Here we present results of a combined Raman and X-ray crystallography approach to study protein crystals. As examples, tetrameric hemoglobins from sub-Antarctic and Antarctic fish (AFHb) exibit an unusual autoxidation pathway [4, 5], and also multiple deoxy and carbomonoxy coordination (unpublished data). Crystallographic data have been supported by Raman microscopy and computational studies providing a clear picture of the complex dynamics of tetrameric hemoglobins. Acknowledgement We acknowledge PRIN and PNRA for financial support.

Code: MP22	Time Slot/Poster Number: 095	Session: Resonance Raman in Biological and Chemical systems
Initial Excited-State Structural Dynamics of 2’-Deoxyguanosine
Amira El-Yazbi; Alexandra Palech ; Glen Loppnow
University of Alberta, Edmonton, Canada

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Summary
To explore the excited-state structural dynamics of 2’-deoxyguanosine, a DNA nucleoside, we measured the resonance Raman spectra of 2’-deoxyguanosine in aqueous solution at wavelengths throughout its absorption band. Self-consistent analysis of the resulting resonance Raman excitation profiles and absorption spectrum using a time-dependent wave packet formalism yielded the excited-state structural dynamics. The N7=C8 stretching and C8-H bending vibrational modes were found to exhibit maximum resonance Raman intensity and structural change upon photoexcitation for 2’-deoxyguanosine, suggesting that the initial dynamics of 2’-deoxyguanosine lie along the oxidative reaction coordinate.

Code: MP22	Time Slot/Poster Number: 096	Session: Resonance Raman in Biological and Chemical systems
Resonance Raman Identification Of A Fe(IV)=O Type Reaction Intermediate During Indoleamine 2, 3-Dioxygenase Reaction
Takashi Ogura¹; Sachiko Yanagisawa¹; Norihiro Okada¹; Masaki Horitani²; Hiroshi Sugimoto²; Yoshitsugu Shiro²; Evan Appelman³
¹University of Hyogo, Ako-Gun, Japan; ²RIKEN SPring-8 Center, Ako-gun, Hyogo, Japan; ³Argonne National Laboratory, Argonne, IL

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Summary
Resonance Raman spectra of indoleamine 2, 3-dioxygenase reaction intermediates are reported. Addition of Trp to the oxygenated intermediate brings about a new spectral species having an absorption band at 593 nm. This "593 nm species" exhibits Raman band at 798 and 762 cm-1 for 16O2 and 18O2, respectively. It then exhibits Raman bands at 798 and 762 cm-1 for 16O18O with half intensities. The results demonstrate that the "593 nm species" has a Fe=O heme. This means that the O-O bond is cleaved during dioxygenation reaction, which is quite inconsistent with the previously proposed mechanism.

Code: MP22	Time Slot/Poster Number: 097	Session: Resonance Raman in Biological and Chemical systems
Resonance Raman Characterization of the Forms of Ground-State 8-Substituted 7-Hydroxyquinoline Caged Acetate Compounds in Aqueous Solutions
Wen Li¹; Hui-Ying An¹; Chensheng Ma¹; Kyle Harris²; Timothy Dore²; David Phillips¹
¹The University of Hong Kong, Hong Kong, Hong Kong; ²University of Georgia, Athens, Georgia

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Summary
8-substituted 7-hydroxyquinolines, like 8-chloro-7-hydroxyquinoline (CHQ) and 8-cyano-7-hydroxyquinoline (CyHQ), are able to be useful for 1PE and 2PE and their acetate acids CHQ−OAc and CyHQ−OAc were also able to undergo photolysis reactions in neutral aqueous buffer solutions. To examine the substituent effect on the relative populations of the forms of the ground state species of 8-substituted 7-hydroxyquinolines, ultraviolet absorption and resonance Raman spectroscopy experiments were done for CHQ–OAc and CyHQ–OAc in differnt solutions.

Code: MP22	Time Slot/Poster Number: 098	Session: Resonance Raman in Biological and Chemical systems
The Hunt for Underlying Electronic Transitions in Peptides: UV Resonance Raman Excitation Profiles and Depolarization Ratios
Bhavya Sharma; Sanford Asher
University of Pittsburgh, Pittsburgh, PA

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Summary
UV resonance Raman spectroscopy is well established as a technique for probing secondary structure of peptides and proteins. Excitation between 180 to 215 nm, within the pi to pi* electronic transitions of the peptide backbone, results in the enhancement of amide vibrations. We use UVRR excitation profiles and Raman depolarization ratio measurements to elucidate the underlying peptide bond electronic transitions.

Code: MP22	Time Slot/Poster Number: 100	Session: Resonance Raman in Biological and Chemical systems
Resonance Raman Studies On Mammalian Cytochromes P450
Piotr Mak¹; James Kincaid¹; Ilia Denisov²; Stephen Sligar²; Haoming Zhang³; Paul Hollenberg³
¹Marquette University, Milwaukee, WI; ²University of Illinois, Urbana-Champaign, IL; ³University of Michigan, Ann Arbor, MI

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Summary
The resonance Raman spectroscopy coupled with cryoradiolysis and nanodisc sampling technology is being applied to study the active site structures of mammalian Cytochromes P450 in their ferric resting states and their CO and O2 ligated forms. Specifically, emphasis is being placed on documenting active site structural changes associated with binding of various substrates, “mechanism-based inhibition” and characterisation of unstable oxo-, peroxo- and hydropeoxo- intermediates that arise within the catalytic cycles of these enzymes.

Code: MP22	Time Slot/Poster Number: 101	Session: Resonance Raman in Biological and Chemical systems
Interrogation of Fibril Aggregation Using UV Resonance Raman Spectroscopy
David Punihaole
University of Pittsburgh, Pittsburgh, PA

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Summary
We use circular dichroism (CD) and UV Resonance Raman (UVRR) spectroscopy to examine the ability of the 21-residue alanine-based peptide AP, A5(AAARA)3A, to form fibrils under high salt conditions. Samples were centrifuged at 5000 rpm, and the solid fibril portion was separated from the liquid. Spectra of both the solid and liquid portions were measured. We find that AP forms stable aggregates in less than 20 minutes when subjected to very high salt concentrations (2M NaCl) conditions and when heated to 70°C.

Code: MP22	Time Slot/Poster Number: 102	Session: Resonance Raman in Biological and Chemical systems
Ultraviolet Resonance Raman Spectroscopy of Adenine Tautomerism In a Gas Phase: Theory and Experiment
Tatiana Burova¹; Galina Ten¹; Roman Scherbakov¹; Igor Lednev²; Vladimir Ermolenkov²
¹Saratov state university, Saratov, Russian Federation; ²University at Albany, Albany, USA

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Summary
We report on resonance Raman spectroscopic study of adenine tautomerism in gas phase at 300° C. Resonance Raman spectra recorded with the excitation at 266, 218 and 200 nm were significantly different relative to each other indicating the resonance enhancement due to various electronic transitions of adenine. Quantum-mechanical calculations were performed to predict resonance Raman spectra of different tautomeric forms of adenine. A comparative analysis of the theoretical results for three tautomeric forms of adenine (Ade-N9Н (аm), Ade-N7Н (am) and Ade-N9Н (im)) with the experimental data allowed for understanding the tautomeric composition of adenine in a gas phase.

Code: MP22	Time Slot/Poster Number: 103	Session: Resonance Raman in Biological and Chemical systems
Glycine-based peptide solution conformational preferences
Sergei Bykov
University of Pittsburgh, Pittsburgh, PA

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Summary
We used UV resonance Raman and visible Raman spectroscopy to investigate the solution conformation of glycine-based peptides in water containing lithium salts for solubility. Our data indicate that conformational preferences of long polygly chains as well as the internal residues of the short oligoglycines are centered around the 3(1) helix Ramachandran angles. We explain this preference by the existence of favorable interactions between carbonyl dipoles in these extended helices.

Code: MP22	Time Slot/Poster Number: 104	Session: Resonance Raman in Biological and Chemical systems
The Role of Solvent in the Hierarchal Structure of a Porphyrin Aggregate
Christopher Rich; Benjamin Friesen; Ursula Mazur; Jeanne McHale
Washington State University, Pullman, WA

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Summary
Resonance Raman and scanning probe microscopy are applied to the study of self-assemblies of tetra-(sulfonatophenyl)porphyrin from aqueous and ethanolic solution. Solvent effects on the relative intensities of the red-shifted (J band) and blue-shifted (H band) components of the split Soret band and differences in the depolarization ratios of low-frequency modes reveal solvent effects on the mesoscale structure of the aggregates. Optical and resonance Raman data are interpreted with a model for excitonic coupling that is based on structural data from scanning probe microscopy.

Code: MP22	Time Slot/Poster Number: 105	Session: Resonance Raman in Biological and Chemical systems
Resonance Raman Spectroscopic Characterization of Live Clownfish (Amphiprion Ocellaris) and their Eggs
Stephen O'Shea¹; Bradford Bourque²; Harold Pomeroy²; Nancy Breen¹
¹Department of Chemistry, Roger Williams University, Bristol, RI; ²Department of Marine Biology, Roger Williams Univ., Bristol, RI

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Summary
The resonance Raman spectrum of the marine ornamental Amphiprion Ocellaris, the common clown fish and their eggs at day 1 and day 4 post spawn are reported. The spectra show the characteristic resonance Raman peaks of the carotenoids near 1525 cm-1and 1158 cm-1. A 4 cm-1 increase is observed in the frequency of the 1525 cm-1 band in the fish eggs from day 1 to day 4. This shift is consistent with the conversion of astaxanthin to zeaxanthin as the eggs develop.

Code: MP22	Time Slot/Poster Number: 106	Session: Resonance Raman in Biological and Chemical systems
UV Resonance Raman Study of the Impact of Salts and Alcohols on Gibbs Free Energy Landscape of an α-helical Peptide
Kan Xiong¹; Eliana Asciutto²; Jeffry Madura²; Sanford Asher¹
¹University of Pittsburgh, Pittsburgh, PA; ²Duquesne University, Pittsburgh, PA

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Summary
We used UV resonance Raman spectroscopy to study the impact of salts and alcohols on Gibbs free energy landscapes of AP of sequence AAAAA(AAARA)3A. NaClO4 stabilizes α-helix-like conformations more than does NaCl, which stabilizes more than Na2SO4 at identical ionic strengths. Much of the NaClO4 α-helix stabilization results from ClO4- association with the AP terminal -NH3+ groups and arg side chains. 2,2,2-trifluroethanol (TFE) most stabilizes α-helix-like conformations, followed by ethanol, methanol and pure water. The π-bulge conformation is stabilized more than the α-helix, while the 310-helix conformation is destabilized due to the alcohol increased hydrophobicity.

Code: MP22	Time Slot/Poster Number: 107	Session: Resonance Raman in Biological and Chemical systems
Dependence of Ethylguanidinium UV Resonance Raman Spectra on the Environment: Insights into the Arginine Sidechain in Peptide and Protein
Zhenmin Hong; Sanford Asher
University of Pittsburgh, Pittsburgh, PA

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Summary
Due to its high selectivity and sensitivity, UV resonance Raman spectroscopy has been applied to study the peptide and protein conformation and folding dynamics. Most of studies have been focused on the backbone structure, while there are relatively less studies about the sidechains. We hereby studied the UV resonance Raman spectra of NH2 rocking band of arginine sidechain and showed that the spectra depends on the environment in which arginine sidechain is. It is a marker to probe local environment of the arginine sidechain.

Code: MP22	Time Slot/Poster Number: 108	Session: Resonance Raman in Biological and Chemical systems
Quantitative UV RR Spectroscopy of Artificial Peptide Receptors
Stephan Niebling¹; Sunil K. Srivastava¹; Christoph Herrmann¹; Peter R. Wich²; Carsten Schmuck²; Sebastian Schlücker¹
¹University of Osnabrueck, Department of Physics, Osnabrueck, Germany; ²University of Duisburg-Essen, Duisburg-Essen, Germany

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Summary
The carboxylate binding subunit (CBS) in artificial peptide receptors can be selectively probed by UV resonance Raman spectroscopy with an excitation wavelength of 275 nm. In conjunction with nonnegative matrix factorization (NMF), this allows to obtain neat component spectra and contributions of the different CBS species in solution. The local pKa of the CBS is accessible via a UV RR pH study after matrix factorization and a Henderson-Hasselbalch fit. This methodology can be extended to UV RR binding studies to determine the binding constant of the receptor (Kass) with a carboxylate or peptide substrate.

Code: MP22	Time Slot/Poster Number: 109	Session: Resonance Raman in Biological and Chemical systems
Localization Of The 1MLCT State Of Novel Ruthenium Polypyridine Complexes Via Resonance Raman Spectroscopy
Michael Schmitt¹; Stefanie Tschierlei¹; Michael Karnahl¹; Benjamin Dietzek^{1, 2}; Sven Rau³; Juergen Popp^{1, 2}
¹Friedrich-Schiller University, Jena, Germany; ²Institute of Photonic Technology, Jena, Germany; ³Friedrich-Alexander University, Erlangen Nürnberg, Germany

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Summary
In this contribution we have characterized the nature of the MLCT state of various different Ruthenium complexes by means of resonance Raman spectroscopy (RR) as a function of different polypyridine ligands. This knowledge is extremely important since the MLCT state is the starting point for all further excited state processes which determine for example the catalytic activity of such complexes. By doing so it could be shown that the photon-to-hydrogen quantum-efficiency of a light-driven RuPd catalyst correlates with the localization of the MLCT state on the Ru-Pd bridging ligand.

Code: MP22	Time Slot/Poster Number: 110	Session: Resonance Raman in Biological and Chemical systems
TD-DFT and Ab Initio Calculations of the High-Energy Materials Ground and Excited States Elucidate the Experimental UV-Raman Data
Nataliya Myshakina; Sanford Asher
University of Pittsburgh, Pittsburgh, PA

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Summary
To improve an understanding of our measured UV-Resonance Raman spectra of high-energy materials we employed high-level electronic structure calculations (TD-DFT, CIS, and CASSCF) to study the ground and the lowest electronic excited states of simple explosive compounds such as isopropyl nitrate and trinitrotoluene. The energies of vertical and adiabatic transitions were calculated together with optimization of geometries corresponding to the lowest excited electronic states. Evaluated geometry displacements occurred due to electronic transitions allows us to predict changes in UV-RR band intensities upon variation of the incident light wavelength.