Nuclear Dynamics

We report the first experimental observation of the pionic fusion of two heavy ions. The 12 C( 12 C, 24 Mg)π 0 and 12 C( 12 C, 24 Na)π + cross sections have been measured to be 208 ± 38 and 182 ± 84 picobarns, respectively, at E cm = 137 MeV. This cross section for heavy-ion pion production, at an energy just 6 MeV above the absolute energy-conservation limit, constrains possible production mechanisms to incorporate the kinetic energy of the entire projectiletarget system as well as the binding energy gained in fusion.

We have studied 12 C in full kinematics via the 10 B( 3 He,pααα) reaction at 2.45 MeV. In our data we have identified states in 12 C from the ground state up to about 18 MeV, with spins ranging from 0 to 4. Due to the very good resolution, we are able to determine properties of these 12 C resonances, such as their energy, width, and spin. In this contribution preliminary results from the ongoing analysis is presented.

We investigate the electron injection from a terrylenebased chromophore to the TiO 2 semiconductor bridged by a recently proposed phenyl-amide-phenyl molecular rectifier. The mechanism of electron transfer is studied by means of quantum dynamics simulations using an extended Huckel Hamiltonian. It is found that the inclusion of the nuclear motion is necessary to observe the photoinduced electron transfer. In particular, the fluctuations of the dihedral angle between the terrylene and the phenyl ring modulate the localization and thus the electronic coupling between the donor and acceptor states involved in the injection process. The electron propagation shows characteristic oscillatory features that correlate with interatomic distance fluctuations in the bridge, which are associated with the vibrational modes driving the process. The understanding of such effects is important for the design of functional dyes with optimal injection and rectification properties.

Intermediate-mass-fragment emission has been studied in central E/A = 30 MeV Xe + " 'Cu reactions. The measured fragment multiplicities, reduced-velocity correlation functions, and emission velocities have been compared with schematic three-body trajectory calculations and with three statistical models with input based upon a dynamical BNV code. The statistical models which include expansion either explicitly or implicitly are able to generate a sufBcient number of fragments. The three-body trajectory calculations indicate a mean emission time of = 200 fm/c, consistent with sequential decay. Dynamical expanding-emitting source calculations predict a similar time scale for fragment emission and give satisfactory agreement with the experimental correlation functions if the experimental angular distributions are incorporated into the model. The Berlin multifragmentation model gives good agreement with the experimental charge distributions, and, depending upon the choice of radius parameter, can provide agreement with either the correlation functions or the fragment emission velocities, but not with both simultaneously. Although an overall good agreement is obtained in the statistical model comparisons, even in the most violent collisions the angular distributions and fragment emission velocities are incompatible with completely equilibrated decay from a single source. PACS uumber(s): 25.70.Pq I. INTR.C)DU CTI(3N Studies of IMF (intermediate mass fragment, 3 & Z ( ) emission have provided a wealth of information about the space-time extent of excited nuclear systems. At high bombarding energy, E/A ) 100 MeV, the frag- ments appear to be emitted on the very short time scale implied by a prompt multi&agment disassembly of heated and expanded nuclear systems . At low bombarding energy, E/A & 20 MeV, standard compound nucleus de- cay accounts for much of the fragment yield following either complete or incomplete fusion reactions [4 -6]. To gain a systematic understanding of the interaction between complex nuclei it is important to characterize the *On leave from the

The exploration of the (Se7en) modalities offers a profound vision for the future, wherein the amalgamation of neuroscience and avant-garde technological innovations heralds a new epoch for augmenting human cognitive capabilities. The integration of advanced computational processes with the human brain, exemplified by the Naturalistic Expansion of a Controlled Cortex (NECC) and Quantum Relay Systems (QRS), comprised of the CCmRNA, HAPTX, NECC, QRS and T-Vector, signify a frontier beyond the current understanding and enhancement of cognitive functions. This essay endeavors to interweave the existing strands of research, navigate the complexities of emerging controversies, and chart novel intersections within the interdisciplinary terrains of neuroscience, technology, and ethics. At the heart of (Se7en) modalities lies the proposition as to how human cognition can be profoundly expanded and enhanced upon, through the synergistic application of cutting-edge technologies. The speculative yet grounded frameworks of CCmRNA, QRS-NFC and the NECC illuminate pathways for transcending biological constraints, thus enabling a deeper comprehension and manipulation of cognitive processes. Such advancements promise not only to redefine the limits of human intelligence and capability but also to address and potentially ameliorate neurological conditions and cognitive impairments. The ramifications of these speculative technologies extend into the realm of ethical, safety, and efficacy considerations. The potential for nanobot-assisted genetic therapy, as suggested by related research, opens Pandora's box of ethical dilemmas and safety concerns which necessitate rigorous scrutiny. In continuation, the pursuit of more durable and biocompatible nanomaterials for medical and cognitive enhancement purposes underscores the pressing need for sustainable technological development within this sphere.

The decay of the giant dipole resonance (GDR) in the 132 Ce compound nucleus with temperature up to 4 MeV has been measured, using the reaction 64 Ni 68 Zn at E beam 300, 400, and 500 MeV. The and charged particles measured in coincidence with recoils are consistent with a fully equilibrated compound nucleus emission. The GDR width, obtained with the statistical model analysis, is found to increase almost linearly with temperature. This increase is rather well reproduced within a model including thermal shape fluctuations and the lifetime of the compound nucleus.

A way to derive rigorous diabatic potentials from non-adiabatic coupling terms NACTs was suggested some time ago w Ž. x M. Baer, Chem. Phys. Lett. 35 1975 112. This approach could be applied only for cases when the NACTs are regular throughout configuration space. In this work a criterion is established to be fulfilled by NACTs which yields continuous and uniquely diabatic potentials defined throughout configuration space. It is found that this requirement leads to a kind of 'quantization' with regard to the non-regular NACTs. A two-state model and a three-state model were considered as examples.

We study the electronic resonant states of H3 with energies above the potential energy surface of the H + 3 ground state. These resonant states are important for the dissociative recombination of H + 3 at higher collision energies, and previous studies have indicated that these resonant states exhibit a triple intersection. We introduce a complex generalization of the pseudo-Jahn-Teller model to describe these resonant states. The potential energies and the autoionization widths of the resonant states are computed with electron scattering calculations using the complex Kohn variational method, and the complex model parameters are extracted by a least-square fit to the results. This treatment results in a non-Hermitian pseudo-Jahn-Teller Hamiltonian describing the system. The nonadiabatic coupling and geometric phase are further calculated and used to characterize the enriched topology of the complex adiabatic potential energy surfaces.

The current decade has seen illuminating and extensive study of interplay of topological effects such as Renner-Teller and Jahn-Teller (JT) effects in small molecules. Study of such effects in HCNH molecule showed an interesting feature that for slightly bent system, a pair of JT conical interactions (CIs) appear only for certain nonplanar configuration, in contrast to its appearance in C S configuration (molecular plane) for C 2 H 2 +. Moreover, since the feature of appearance of JT-CIs in two 2 + states of HCNH in some bent configuration may be critically associated to the abundance of HNC in interstellar spaces, as advocated recently by Das and Mukhopadhyay (J. Phys. Chem. 117, 8680 (2013)), the interest in such topological studies have remained relevant. In this article we have investigated such topological effects for slightly bent N 2 H 2 + and HBNH +. Interestingly, the appearance of JT-CIs are, for HBNH + , in molecular plane while for N 2 H 2 + , in certain nonplanar configuration, in sharp contrast to the effect in the otherwise similar pair of molecular systems, C 2 H 2 + and HCNH.

So far, most studies of the geometric phase effect have presumed that the phase is path-independent; hence, one must supply another restriction concerning the boundary condition on the nuclear wave functions when dealing with nonsymmetric isotopomers of X 3 systems. We report calculations of the vibrational spectra of HD 2 using a recently proposed generalized Born-Oppenheimer (GBO) formalism. The calculations demonstrate that there are significant differences between the results calculated from the present GBO method and those based on the preceding presumption.

The real-time dynamics in the excited electronic B state of the Na3 cluster (Na3(B)) in a supersonic beam were investigated in time-resolved two-photon ionization (TPI) experiments, using the picosecond pump-and-probe technique followed by mass-selective detection. The time-dependent TPI signal reflects the evolution of the pseudorotation in the B state. The observed beat structure has a period of 3 ps, complementary to the energy level structure of thecontinuous-wave (CW) TPI absorption spectrum. These results arecompared with theoretical calculations based on a simple two-dimensional model of the vibrating/pseudorotating sodium trimer. The molecular dynamics of Na3 (B) is simulated by the representative time-dependent wavepacket. The resulting autocorrelation function and its Fourier transform correspond to the experimental time-dependent and timeindependent spectra, respectively. The ab initio potential energy surface (PES) served as a guidance for constructing model PES which demonstrate that the theoretical spectra are sensitive to the potential energy surface along the path from the obtuse isosceles to the acute triangle configuration of Nas(B) and to the corresponding potential energy barrier. A qualitative agreement with the experimental spectra is obtained for low barriers (ca. 0-15 cm-l) and nearly circular form of the PES. The results provide the starting point for more realistic three-dimensional model simulations of the pseudorotating Na3(B).

It is a talk at 15-th Winter Workshop on Nuclear Dynamics, Parkcity Utah, Jan.1999. Because too many interesting things are going on now, I have tried to squeeze three different subjects into one talk. The first is a brief summary of the color super-conductivity. During the last year we learned that instanton-induced forces can not only break chiral symmetry in the QCD vacuum, but also create correlated scalar diquarks and form new phases, some similar to the Higgs phase of the Standard model. The second issue I discuss is the remnant of the so called tricritical point, which in QCD with physical masses is the endpoint of the first order transition. I will argue that exchange of sigmas (which are massless at this point even with quark masses included) create interesting event-by-event fluctuations, which can be used to locate it. Finally I describe first results in f low calculations for non-central collisions at RHIC. It was found that it is extremely sensitive to Equation of State (EOS). Furthermore, the unusual "nutcracker" picture emerges for lattice-motivated EOS, which is formation of two shells which are physically separated bef ore the freezeout.

When a set of three states appears strongly coupled within the set but interacts very weekly with other states of the Hilbert space, these three states form a sub-Hilbert space and thereby, one can express the non-adiabatic coupling (NAC) elements in terms of adiabatic-diabatic transformation (ADT)/mixing angles obviously representing the same sub-space It has been possible to demonstrate that those explicit forms of the NAC terms satisfy the Curl equations-the necessary conditions to ensure the adiabatic-diabatic transformation in order to remove the NAC terms (could be singular also at specific point(s) or along a seam in the configuration space) in the adiabatic representation of nuclear SE and to obtain the diabatic one with smooth functional form of coupling elements among the electronic states. While formulating the extended Born-Oppenheimer (EBO) equations [J Chem Phys 124 074101 (2006)] for the ground adiabatic state, we demonstrate the necessity for the existence of zero Curls of the NAC terms and discuss briefly about their analytical validity at and around the conical intersection Considering a three state diabatic Hamiltonian, namely, the so called induced Renner-Teller model, we calculate the NAC terms and their Curls analytically, and explore the nature of these quantities, when the three states are either degenerate at a point or approaching to form three states degeneracy at the same point.

An extended Longuet-Higgins formalism recently utilized to obtain generalized Born-Oppenheimer equations including the geometrical phase effect has been used to study a threefold pseudo-Jahn-Teller type electronic degeneracy. The results of dynamics calculations carried out with the novel formalism are compared with Born-Oppenheimer (geometrical phase ignored), extended Born-Oppenheimer, and coupled three-state ones for the same system. The theory shows unprecedented simplicity while depicting all features.

We present explicit form of non-adiabatic coupling (NAC) elements of nuclear Schroedinger equation (SE) for a coupled tri-state electronic manifold in terms of mixing angles of real electronic basis functions. If the adiabatic-diabatic transformation (ADT) angles are the mixing angles of electronic basis, ADT matrix transforms NAC terms to exactly zeros and brings diabatic form of SE. ADT and NAC matrices satisfy a curl condition and find a novel relation among the mixing angles for irrotational case. We also find that extended Born-Oppenheimer (EBO) equations have meaningful solution and can reproduce numerically exact results only when the equations are gauge invariant.

In recent years, multifragmentation of nuclear systems has been extensively studied, and many efforts have been made to clarify the underlying physics. However, no clear consensus exists on the mechanism for multifragmentation. Is the emission of intermediate mass fragments (IMF: 3 {le} Z {le} 20) a dynamical process (brought on by the occurrence of instabilities of one form or another) or a statistical process (i.e. the decay probabilities are proportional to a suitably defined exit channel phase space)? Historically the charge (mass) distribution has played and still plays a very important role in characterizing multifragmentation. Since this subject`s inception, the near power-law shape of the charge and mass distributions was considered an indication of criticality for the hot nuclear fluid produced in light ion and heavy ion collisions. Here, the authors have studied different aspects of the charge distributions. The implications of the experimental evidence presented here are ...

We report calculations of the vibrational spectrum of HD 2 in its first-excited electronic state by using a coordinate-transformation technique. The implications of the geometric phase (GP) effect in the spectrum have been investigated. The results show that the lowest 45 vibrational levels calculated using the traditional Longuet-Higgins phase (φ/2, where φ is the pseudorotation angle) are in good agreement with those obtained by using a single-surface generalized Born-Oppenheimer equation previously reported by the authors.

The decay of the Isoscalar Giant Monopole Resonance (ISGMR) in nuclei is studied by means of a nonlinear classical model consisting of several noninteracting nucleons (particles) moving in a potential well with an oscillating nuclear surface (wall). The motion of the nuclear surface is described by means of a collective variable which appears explicitly in the Hamiltonian as an additional degree of freedom. The total energy of the system is therefore conserved. Although the particles do not directly interact with each other, their motions are indirectly coupled by means of their interaction with the moving nuclear surface. We consider as free parameters in this model the degree of collectivity and the fraction of nucleons that participate to the decay of the collective excitation. Specifically, we have calculated the decay width of the ISGMR in the spherical nuclei 208 Pb, 144 Sm, 116 Sn and 90 Zr. Despite its simplicity and its purely classical nature, the model reproduces the trend of the experimental data which show that with increasing mass number the decay width decreases. Moreover the experimental results (with the exception of 90 Zr) can be well fitted using appropriate values for the free parameters mentioned above. It is also found that these values allow for a good description of the experimentally measured 112 Sn and 124 Sn decay widths. In addition, we give a prediction for the decay width of the exotic isotope 132 Sn for which there is experimental interest. The agreement of our results with the corresponding experimental data for medium-heavy nuclei is dictated by the underlying classical mechanics i.e. the behaviour of the maximum Lyapunov exponent as a function of the system size.

The decay of the Isoscalar Giant Monopole Resonance (ISGMR) in nuclei is studied by means of a nonlinear classical model consisting of several noninteracting nucleons (particles) moving in a potential well with an oscillating nuclear surface (wall). The motion of the nuclear surface is described by means of a collective variable which appears explicitly in the Hamiltonian as an additional degree of freedom. The total energy of the system is therefore conserved. Although the particles do not directly interact with each other, their motions are indirectly coupled by means of their interaction with the moving nuclear surface. We consider as free parameters in this model the degree of collectivity and the fraction of nucleons that participate to the decay of the collective excitation. Specifically, we have calculated the decay width of the ISGMR in the spherical nuclei 208 Pb, 144 Sm, 116 Sn and 90 Zr. Despite its simplicity and its purely classical nature, the model reproduces the trend of the experimental data which show that with increasing mass number the decay width decreases. Moreover the experimental results (with the exception of 90 Zr) can be well fitted using appropriate values for the free parameters mentioned above. It is also found that these values allow for a good description of the experimentally measured 112 Sn and 124 Sn decay widths. In addition, we give a prediction for the decay width of the exotic isotope 132 Sn for which there is experimental interest. The agreement of our results with the corresponding experimental data for medium-heavy nuclei is dictated by the underlying classical mechanics i.e. the behaviour of the maximum Lyapunov exponent as a function of the system size.

The nonadiabatic couplings which arise when two potential energy surfaces of a polyatomic molecule get close in energy can be classified as follows: (A) avoided crossings, (B) genuine intersections (Jahn-Teller and conical), (C) glancing intersections (Renner-Teller interactions). The characteristics of the potential energy surfaces in the adiabatic and diabatic representations are discussed for each case. The three coupling cases differ in the structure of the Hamiltonian matrix. When the latter is written in the diabatic representation, it is meaningful to retain the leading term only in its power series expansion. This gives rise to a so-called minimum-order model which is found to be surprisingly accurate (at least in a restricted zone of nuclear coordinates) when compared to the results of ab initio calculations. The characteristic features of each coupling case can only be understood in a two-dimensional configuration space, Le., when two nuclear degrees of freedom, often with different symmetry properties, are explicitly considered. A simple expression of the nonadiabatic transition probability between two electronic states can be worked out in the framework of the minimum-order models. Two-dimensional extensions of the Landau-Zener formula are obtained, which can be used to study the consequences of the anisotropic properties of the coupling. In the case of avoided crossings, only nuclear trajectories having a well-defined direction are able to bring about surface hopping, wheras there exists two active degrees of freedom for conical intersections. Hence, nonadiabatic processes which are controlled by genuine intersections are expected to take place faster than those controlled by avoided crossings.

The Time Dependent Discrete Variable Representation (TDDVR) method was initiated by Adhikari and Billing considering time dependent Gauss-Hermite basis functions, where all the parameters were assumed to be time dependent. Adhikari et al. had reformulated the TDDVR approach considering the width parameter as time independent, whereas the equation of motion for time dependent parameters (center of wave packet and its momentum) are derived from Dirac-Frenkel variational principle. Such a method is computationally efficient due to its inherent parallelizable nature to perform multistate (electronic) multidimensional (vibrational) quantum dynamics for well-converged results within reasonably fast computation time, where the complexity of the Hamiltonian is not a matter of concern. Its parallel version is computationally efficient as compared to other quantum dynamical method like the multiconfiguration time dependent Hartree (MCTDH). The parallelized version of this method has also been employed to different complex dynamical systems to calculate transition probabilities, tunnelling probabilities, inelastic surface scattering, bi-molecular reactive scattering and photoexcitation. We have also made use of TDDVR methodology successfully to different diatom (H 2 /D 2)-metal surface (Cu/Ni) scattering processes and triatomic reaction dynamics by using 3D time dependent wave packet approach in hyperspherical coordinates to calculate state-tostate reaction probabilities of D+H 2 reaction for J = 0 case.

Within the framework of flow and multifragmentation study, the 36 Ar+ 58 Ni experiment has been performed at seven incident energies from 32 to 95 A • MeV with the INDRA detector at GANIL. After a brief description of the experimental setup , the main trends as well as the evolution of fragment distributions will be presented. Some results about reaction mechanisms for particular classes of events will conclude this report.

Protons and a-particles emitted from the compound nucleus 179Au excited to 26 MeV were detected in coincidence with the corresponding evaporation residues. The charged-particle spectra are shifted to lower energies than spectra from statistical-model calculations based on a spherical compound nucleus.

Intermediate-mass-fragment emission has been studied in central E/A = 30 MeV Xe + " 'Cu reactions. The measured fragment multiplicities, reduced-velocity correlation functions, and emission velocities have been compared with schematic three-body trajectory calculations and with three statistical models with input based upon a dynamical BNV code. The statistical models which include expansion either explicitly or implicitly are able to generate a sufBcient number of fragments. The three-body trajectory calculations indicate a mean emission time of = 200 fm/c, consistent with sequential decay. Dynamical expanding-emitting source calculations predict a similar time scale for fragment emission and give satisfactory agreement with the experimental correlation functions if the experimental angular distributions are incorporated into the model. The Berlin multifragmentation model gives good agreement with the experimental charge distributions, and, depending upon the choice of radius parameter, can provide agreement with either the correlation functions or the fragment emission velocities, but not with both simultaneously. Although an overall good agreement is obtained in the statistical model comparisons, even in the most violent collisions the angular distributions and fragment emission velocities are incompatible with completely equilibrated decay from a single source. PACS uumber(s): 25.70.Pq I. INTR.C)DU CTI(3N Studies of IMF (intermediate mass fragment, 3 & Z (20) emission [1] have provided a wealth of information about the space-time extent of excited nuclear systems. At high bombarding energy, E/A) 100 MeV, the fragments appear to be emitted on the very short time scale implied by a prompt multi&agment disassembly of heated and expanded nuclear systems [2,3]. At low bombarding energy, E/A & 20 MeV, standard compound nucleus decay accounts for much of the fragment yield following either complete or incomplete fusion reactions [4-6]. To gain a systematic understanding of the interaction between complex nuclei it is important to characterize the

The giant dipole resonance built on excited states was studied in " '" Sn nuclei at excitation energies of 62, 80, 110, and 130 MeV, by measuring y rays following heavy ion fusion reactions ' 0+ "Mo and ' F+ 'Nb. The energy of the dipole resonance was found to be 14.8+0.4 MeV independent of excitation energy. This value is approximately 1 MeV below the extrapolated ground state value. The width increases almost quadratically from 6.7 MeV at 62 MeV to 10.8 MeV at 130 MeV. This agrees qualitatively with a theoretical prediction that the increase in width for these nuclei is mainly due to an averaging of strength functions over various oblate shapes induced at high spin and temperature. The sensitivity to the isovector quadrupole vibration was found to be small even at the highest excitation energy. No convincing conclusion could be made for its existence in these Sn nuclei.

The current decade has seen illuminating and extensive study of interplay of topological effects such as Renner-Teller and Jahn-Teller (JT) effects in small molecules. Study of such effects in HCNH molecule showed an interesting feature that for slightly bent system, a pair of JT conical interactions (CIs) appear only for certain nonplanar configuration, in contrast to its appearance in C S configuration (molecular plane) for C 2 H 2 +. Moreover, since the feature of appearance of JT-CIs in two 2 + states of HCNH in some bent configuration may be critically associated to the abundance of HNC in interstellar spaces, as advocated recently by Das and Mukhopadhyay (J. Phys. Chem. 117, 8680 (2013)), the interest in such topological studies have remained relevant. In this article we have investigated such topological effects for slightly bent N 2 H 2 + and HBNH +. Interestingly, the appearance of JT-CIs are, for HBNH + , in molecular plane while for N 2 H 2 + , in certain nonplanar configuration, in sharp contrast to the effect in the otherwise similar pair of molecular systems, C 2 H 2 + and HCNH.

Search for configuration space with well-defined topological (Berry) phases corresponding to Jahn-Teller (JT) conical intersection (CI) and Renner-Teller(RT) parabolic intersection (PI) in the linear tetra-atomic molecular system on introduction of bending, reveal the interesting aspect that these potential intersections may appear in molecular plane as well as out of the molecular plane. While understanding this aspect is important for following the class of phenomena led by potential intersections, till date studies on molecular systems including pairs like (C 2 H 2 + , HCNH) as well as (N 2 H 2 + , HBNH +), have not been able to clarify the issue. The present paper embodies calculation of non-adiabatic coupling terms (NACT's) involving four low-lying states of slightly bent HCNO + , a motivated choice of tetra-atomic with all four different atoms, to study this aspect associated with JT-CI and RT-PI in slightly bent linear system. The plane of appearance of these effects, has been advocated to be related to electronic configuration of the concerned states of the molecular system.

The experiments were performed with an array of 12 detectors which together covered a large fraction of the forward hemisphere and allowed a high detection efficiency for these events. Masses and energies of all fragments have been reconstructed by means of an improved version of the kinematic coincidence method. The probabilities P~ and P4 of producing 3-and 4-body events were found to depend mainly on the dissipated energy rather than on the bombarding energy, thus indicating that their origin lies more in the decay properties of the excited fragments than in the dynamics of the interaction. Emission of light particles from the composite system is shown to become more relevant with increasing bombarding energy and may explain the drop of the P3 and P4 curves at high energy losses. Small deviations of the P3 and P4 curves at 23.7 A. MeV from those at lower bombarding energies were used to estimate the amount of a possible pre-equilibrium light particle emission as a function of impact parameter.

In 1985, Robert Curl and Richard SmaJleyl discovered a new form of carbon, the fullerene, Cm, which consists of 60 carbon atoms in a closed cage resembling a soccer ball. In 1990, Kriitschmer et al. were able to make macroscopic quantities of fderenes2.

Fluorescence recovery after photobleaching (FRAP) has become a popular technique to investigate the behavior of proteins in living cells. Although the technique is relatively old, its application to studying endogenous intracellular proteins in living cells is relatively recent and is a consequence of the newly developed fluorescent protein-based living cell protein tags. This is particularly true for nuclear proteins, in which endogenous protein mobility has only recently been studied. Here we examine the experimental design and analysis of FRAP experiments. Mathematical modeling of FRAP data enables the experimentalist to extract information such as the association and dissociation constants, distribution of a protein between mobile and immobilized pools, and the effective diffusion coefficient of the molecule under study. As experimentalists begin to dissect the relative influence of protein domains within individual proteins, this approach will allow a quantitative assessment of the relative influences of different molecular interactions on the steady-state distribution and protein function in vivo.

Within the framework of flow and multifragmentation study, the 36 Ar+ 58 Ni experiment has been performed at seven incident energies from 32 to 95 A • MeV with the INDRA detector at GANIL. After a brief description of the experimental setup , the main trends as well as the evolution of fragment distributions will be presented. Some results about reaction mechanisms for particular classes of events will conclude this report.

Recent experiments performed at GANIL with a crystal blocking technique have shown direct evidences of long fission times in the Super-Heavy Elements (SHE) region. Aimed to localize the SHE island of stability, can these experiments give access to the fission barrier and then to the shell-correction energy? In this paper, we calculate the fission time of heavy elements by using a new code, KEWPIE2, devoted to the study of the SHE. We also investigate the effect of potential structure beyond the saddle on the fission time.

The vibronic origin of instability of the symmetrical forms (D¥ h, C2h and C2v) of the hydrogen peroxide molecule H2O2 was revealed using ab initio calculations of the electronic structure and the adiabatic potential energy curves. The vibronic constants in this approach were estimated by fitting of the ab initio calculated adiabatic potential in the vicinity of the high-symmetry nuclear configurations to its analytical expression. It was shown that the equilibrium "skewed" anticline shape of the C2 symmetry can be realized in two ways: D¥h ® C2v® C2 or D¥h ® C2h® C2 with the decreasing of the adiabatic potential energy at every step.

Diabatization of the molecular Hamiltonian is a standard approach to remove the singularities of nonadiabatic couplings at conical intersections of adiabatic potential energy surfaces. In general, it is impossible to eliminate the nonadiabatic couplings entirely-the resulting "quasidiabatic" states are still coupled by smaller but nonvanishing residual nonadiabatic couplings, which are typically neglected. Here, we propose a general method for assessing the validity of this potentially drastic approximation by comparing quantum dynamics simulated either with or without the residual couplings. To make the numerical errors negligible to the errors due to neglecting the residual couplings, we use the highly accurate and general eighth-order composition of the implicit midpoint method. The usefulness of the proposed method is demonstrated on nonadiabatic simulations in the cubic Jahn-Teller model of nitrogen trioxide and in the induced Renner-Teller model of hydrogen cyanide. ...

We present the molecular symmetry (MS) adapted treatment of nonadiabatic coupling terms (NACTs) for the excited electronic states (2 2 E′ and 1 2 A 1 ′) of Na 3 cluster, where the adiabatic potential energy surfaces (PESs) and the NACTs are calculated at the MRCI level by using an ab initio quantum chemistry package (MOLPRO). The signs of the NACTs at each point of the configuration space (CS) are determined by employing appropriate irreducible representations (IREPs) arising due to MS group, and such terms are incorporated into the adiabatic to diabatic transformation (ADT) equations to obtain the ADT angles. Since those sign corrected NACTs and the corresponding ADT angles demonstrate the validity of curl condition for the existence of three-state (2 2 E′ and 1 2 A 1 ′) sub-Hilbert space, it becomes possible to construct the continuous, single-valued, symmetric, and smooth 3 × 3 diabatic Hamiltonian matrix. Finally, nuclear dynamics has been carried out on such diabatic surfaces to explore whether our MS-based treatment of diabatization can reproduce the pattern of the experimental spectrum for system B of Na 3 cluster.

The submitted rnanuscnpt has been creatc by the Universcty of Chicago as Operator Argonne National Laboratory ('Argonne under Contract No. W-31-109-ENG38 wr the US. Department of Energy. The U.: Government retains for itself, and others ac ing on its behalf, a paid-up, nonexclusiv irrevocable worldwide license in said artic to reproduce, prepare derivahe works. di tribute copies to the p d i c , and perform pu licly and display publicly, by or on behalf the Government. DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, rccommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.

Within the framework of flow and multifragmentation study, the 36 Ar+58Ni experiment has been performed at seven incident energies from 32 to 95 AMeV with the INDRA detector at GANIL. After a brief description of the experimental set-up, the main trends as well as the evolution of fragment distributions will be presented. Some results about reaction mechanisms for particular classes of events will conclude this report.