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Contents FRONTIERS ARTICLE 1–8 State-selected ion–molecule reactions with Coulomb-crystallized molecular ions in traps Xin Tong, Tibor Nagy, Juvenal Yosa Reyes, Matthias Germann, Markus Meuwly, Stefan Willitsch Research highlights " First study of an ion–molecule reaction using state-selected, spatially localized molecular ions at milliKelvin temperatures. " Rovibrational-state preparation/ resolution for reactant/product ions. " Characterization of translation-to-rotation energy transfer upon charge exchange between N þ 2 and N 2 . " Experimental results interpreted with classical trajectory simulations on a full-dimensional PES. EDITOR'S CHOICE 9–12 Phase transition of ice I c to ice XI under electron beam irradiation Keita Kobayashi, Hidehiro Yasuda Research highlights " The phase transition of ice I c to ice XI under electron beam irradiation was observed by TEM. " The phase transition occurs on the time-scale of a laboratory experiment. " We argue that the phase transition to ice XI readily occurs in outer space, contrary to the prevailing notion. GASEOUS MOLECULES 13–20 Femtosecond ionization and Coulomb explosion of small transition metal carbide clusters Matt W. Ross, A.W. Castleman Jr. Research highlights " Strong-field ionization of small group 5 metal carbides explored. " More efficient Coulomb explosion observed from V < Nb < Ta. " Ionization enhancement observed to occur in each system. " Ionization behavior of metal carbides vs. metal oxides compared. Elsevier B.V. doi:10.1016/S0009-2614(12)01003-2 Volume 547, iii–viii Contents lists available at ScienceDirect Chemical Physics Letters journal homepage: www.elsevier.com/locate/cplett

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Page 1: Contents

Contents

FRONTIERS ARTICLE

1–8

State-selected ion–molecule reactions with Coulomb-crystallizedmolecular ions in traps

Xin Tong, Tibor Nagy, Juvenal Yosa Reyes, Matthias Germann,Markus Meuwly, Stefan Willitsch

Research highlights " First study of an ion–molecule reaction using state-selected, spatiallylocalized molecular ions at milliKelvin temperatures. " Rovibrational-state preparation/resolution for reactant/product ions. " Characterization of translation-to-rotation energytransfer upon charge exchange between Nþ2 and N2. " Experimental results interpreted withclassical trajectory simulations on a full-dimensional PES.

EDITOR'S CHOICE

9–12

Phase transition of ice Ic to ice XI under electron beam irradiation

Keita Kobayashi, Hidehiro Yasuda

Research highlights " The phase transition of ice Ic to ice XI under electron beam irradiationwas observed by TEM. " The phase transition occurs on the time-scale of a laboratoryexperiment. " We argue that the phase transition to ice XI readily occurs in outer space,contrary to the prevailing notion.

GASEOUS MOLECULES

13–20

Femtosecond ionization and Coulomb explosion of smalltransition metal carbide clusters

Matt W. Ross, A.W. Castleman Jr.

Research highlights " Strong-field ionization of small group 5 metal carbides explored." More efficient Coulomb explosion observed from V < Nb < Ta. " Ionization enhancementobserved to occur in each system. " Ionization behavior of metal carbides vs. metal oxidescompared.

Elsevier B.V.doi:10.1016/S0009-2614(12)01003-2

Volume 547, iii–viii

Contents lists available at ScienceDirect

Chemical Physics Letters

journal homepage: www.elsevier .com/locate /cplet t

Page 2: Contents

21–23

Laser induced fluorescence spectroscopy of rutheniummonoboride

Na Wang, Y.W. Ng, A.S.-C. Cheung

Research highlights " Gas-phase RuB molecule is formed from the reaction of Ru atom anddiborane. " Laser induced fluorescence spectrum of RuB observed. " Three electronictransition bands were observed and analyzed. " Identification of the X2D5/2 ground stateand determination of molecular constants.

CONDENSED PHASES

24–29

Dimer self-association via hydrogen bonding: Measurement andcomparison of binding constants with 2-amidopyrimidinederivatives

Victor Bednar, K. Wade Elliott, Emily Byrd, Jeffrey N. Woodford

Research highlights " New self-assembling derivatives of 2-amidopyrimidine weresynthesized. " The association constant for self-assembly was measured via NMR." The derivatives with the largest alkyl chains had the lowest association constants." DFT results show possible connection to amide syn/anti isomerization.

30–34

Network connectivity and extended Se chains in the atomicstructure of glassy GeSe4

Kateryna Sykina, Eric Furet, Bruno Bureau, S�bastien Le Roux,Carlo Massobrio

Research highlights " Glassy GeSe4 structure was investigated using molecular dynamicssimulations. " We report the existence of long Se chains interconnecting GeSe4 tetrahedra." The homogeneous model consisting of GeSe4 tetrahedra can be discarded. " A pure phaseseparation model (GeSe2 and Se) is also highly unlikely. " Different functionals (PW andPBE) lead to consistent structural results.

35–37

Positronium in alkanes. From neat nonadecane to wax

Bo _zena Zgardzinska, Tomasz Goworek

Research highlights " Positron annihilation allows to determine the phase transition pointsin alkanes. " The range of rotator phase increases with broadening the alkane composition." The same concerns the range of crystal-rotator coexistence range. " Positroniumformation with trapped electrons disappears in multicomponent mixtures.

iv Contents

Page 3: Contents

NANOSTRUCTURES AND MATERIALS

38–41

Fluorescence quantum efficiency dependent on the concentrationof Nd3+ doped phosphate glass

A.A. Andrade, V. Pilla, S.A. LourenÅo, A.C.A. Silva, N.O. Dantas

Research highlights " We studied a new phosphate glass doped with Nd3+. " Studies wereperformed in function of Nd3+ concentration (0.5–3 � 1020 ions/cm3). " The thermalproperties of the phosphate glass were determined. " The fluorescence quantum efficiencyin function of Nd3+ concentration was determined.

0.5 1.0 1.5 2.0 2.5 3.0 3.50.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0λexc = 514nm

τ/τ0

η

Nd3+ (1020 ions/cm3)

42–46

Transformation of non-orthogonal X-junction of single-walledcarbon nanotubes into parallel junction by heating

Xueming Yang, Pu Zhang, Zhonghe Han, Dongci Chen,Albert C. To

Research highlights " Non-orthogonal X-junctions of UTCNTs are prone to transform intoparallel-junction by heating at high temperature. " The torque and the correspondingangular displacement of the UTCNTs in this transformation are analyzed. " Thetransformation is a result of the torque originating from the heating of the non-orthogonalX-junction.

47–51

Single-molecule fluorescence of terrylene embedded inanthracene matrix: A room temperature study

M. Yavuz Y�ce, Alper Kiraz

Research highlights " Terrylene-doped anthracene thin films were obtained by spin coating." Fluorescence lifetime measured to be 3.6 ns; shorter than those in other hosts." Terrylene molecules were oriented nearly parallel to the substrate. " Typical fluorescencedetection rates at saturation were »750 kHz. " Our results complement previous studies onterrylene–anthracene at low temperatures.

52–57

Construction of Au nanoparticle/ferritin satellite nanostructure

Bin Zheng, Mutsunori Uenuma, Naofumi Okamoto,Ryoichi Honda, Yasuaki Ishikawa, Yukiharu Uraoka,Ichiro Yamashita

Research highlights " Au nanoparticle/ferritin satellite nanostructures are constructed." Nanoparticles in the satellite nanostructure are interchangeable. " Au nanoparticle/ferritin satellite nanostructure was selective to Ti surface.

Contents v

Page 4: Contents

58–62

Cushioning effect, enhanced localized plastic flow and thermaltransport in SWCNT–lead silicate glass composite

S. Ghosh, A. Ghosh, T. Kar, S. Das, P.K. Das, R. Banerjee

Research highlights " Single walled carbon nanotubes are embedded in lead silicate glass bymelt–quench technique. " The composite shows enhanced hardness, toughness and thermalconductivity than the glass. " Cushioning behavior of agglomerated SWCNT bundleseffectively enhanced the hardness of the composite. " Crack bridging and accumulation ofSWCNT bundles were responsible for improved fracture toughness of the composite. " Thethermal conductivity of the composite increased due to incorporation of SWCNT in glass.

BIOMOLECULES

63–65

Bambus[6]uril as a novel macrocyclic receptor for the cyanideanion

Petr Toman, Emanuel Makrl�k, Petr Vanura

Research highlights " Quantum mechanical DFT calculations were used. " The structure ofthe novel anionic complex bambus[6]uril�CN� was derived. " The CN� anion is bound by 12weak H-bonds in the macrocyclic cavity. " The interaction energy of the resulting complexwas found to be �324.3 kJ mol�1.

66–72

Computational studies of dielectric permittivity effects onchemical shifts of alanine dipeptide

Aleksandr B. Sahakyan

Research highlights " A peptide model is used to study non-specific solvent effects onchemical shifts. " Chemical shifts are highly sensitive to dielectric constant, e, of themedium. " The dependence can be approximated as an effect of the solvent reaction field." Small deviation of e at the low-value region can induce large chemical shift changes." Averaged backbone chemical shifts suggest low effective e for protein interior.

73–81

Analysis of DNA deformation patterns in nucleosome coreparticles based on isometric feature mapping and continuouswavelet transform

Xi Yang, Hong Yan

Research highlights " A collective structural signal is extracted from the NCP DNA pathusing Isomap. " The signal accounts for the coupled slide–roll–twist behavior. " Thehigh-frequency feature of the structural signal is consistent for all the NCPs. " The low-frequency feature of the structural signal reveals individual differences. " Peaks and valleysof fluctuation energy are enriched in GC and AC/GT, respectively.

vi Contents

Page 5: Contents

82–88

Variation of conformational properties at a glance. True graphicalvisualization of the Ramachandran surface topology as a periodicpotential energy surface

Imre J�kli, Svend J. Knak Jensen, Imre G. Csizmadia, Andr�s Perczel

Research highlights " A new way to visualize the Ramachandran map of peptides ispresented. " The periodicity of the dihedral angles makes a toroidal coordinate system anatural choice. " Color coding of a 2-torus facilitates identification of desirable properties.

89–96

Ab initio molecular simulations on specific interactions betweenamyloid beta and monosaccharides

Kazuya Nomura, Akisumi Okamoto, Atsushi Yano, Shin'ichi Higai,Takashi Kondo, Seiji Kamba, Noriyuki Kurita

Research highlights " We investigate specific interactions between amyloid b Ab (1–42) andsugar. " Two types of Ab structures are constructed based on NMR structures. " Stablestructure of the solvated complex of Ab with sugar is obtained. " The b-sheet Ab bindssugars more strongly than the a-helix Ab. " Sugar V composed of three SO3

� groups bindsmost strongly to the b-sheet Ab.

1.8Å

Tyr10

Hip14

Sugar V1.8

2.5

2.32.5

3.6

1.8Å

Tyr10

Hip14

Sugar V1.8

2.5

2.32.5

3.6

NEW EXPERIMENTAL OR THEORETICAL METHODS

97–102

Theoretical study of the hydrolysis of ethyl benzoate in acidicaqueous solution using the QM/MC/FEP method

Thanayuth Kaweetirawatt, Yohei Kokita, Shiho Iwai,Michinori Sumimoto, Kenji Hori

Research highlights " We investigated the hydrolysis of ethyl benzoate by the QM/MC/FEPmethod. " The diffuse functions affected directly on geometries and energies of calculation." The model including 2 waters (2W) cannot represent the mechanism of the hydrolysis." The 3rd water molecule (3W model) is necessary and its position is very important." The DG� value of 3W model is consistent with the experiment within 1.0 kcal mol�1.

103–109

Low-power broadband homonuclear dipolar recoupling withoutdecoupling: Double-quantum 13C NMR correlations at very fastmagic-angle spinning

Gholamhasan Teymoori, Bholanath Pahari, Baltzar Stevensson,Mattias Ed�n

Research highlights " New series of homonuclear 2Q recoupling sequences for fast-MASNMR operation. " Each pulse-sequence member is generated recursively and requires verylow rf power. " A high-order average Hamiltonian analysis predicts progressively improvedresonance-offset compensation. " The theoretical predictions are verified experimentallyand numerically. " A 2Q–1Q correlation NMR experiment is demonstrated on[U–13C]tyrosine.

Contents vii

Page 6: Contents

110–113

Estimation of AOT and SDS CMC in a methanol usingconductometry, viscometry and pyrene fluorescencespectroscopy methods

Anastasios I. Mitsionis, Tiverios C. Vaimakis

Research highlights " Surfactant molecule geometry affects the micelle formation. " Pyrenefluorescence spectroscopy and conductometry showed almost similar results. " Viscometryis considered to be the less effective method. " The estimated CMCs in methanol werehigher compared to those in water.

114–119

On-the-fly free energy parameterization via temperatureaccelerated molecular dynamics

Cameron F. Abrams, Eric Vanden-Eijnden

Research highlights " Our method can determine parameters of a free energy in molecularsimulations. " Free-energy gradients from temperature-accelerated MD are used on-the-fly." We demonstrate our method in derived effective potentials for coarse-grainedsimulations.

The Publisher encourages the submission of articles in electronic form thus saving time and avoiding rekeying errors.Please refer to the online version of the Guide for Authors at http://www.elsevier.com/locate/cplett

Full text of this journal is available, on-line from ScienceDirect. Visit www.sciencedirect.com for more information.

120–126

Atomic size, ionization energy, polarizability, asymptoticbehavior, and the Slater–Zener model

Roger L. DeKock, John R. Strikwerda, Eric X. Yu

Research highlights " Slater–Zener model to relate atomic size to atomic ionization energy." Effective atomic size related to atomic polarizability. " Error in previous derivation ofatomic size related to ionization energy is spelled out. " The utility of the new relationshipbetween size and ionization energy is spelled out.

viii Contents