01675nas a2200241   4500008004100000022001400041245009400055210006900149260000900218490000800227520077000235653006901005653003901074653002001113653005701133653002001190100002401210700002701234700001601261700001801277700001601295856012201311       2020                        eng d  a0026-897600aShape resonance of sulphur dioxide anion excited states using the CAP-CIP-FSMRCCSD method0 aShape resonance of sulphur dioxide anion excited states using th  cAUG 0 v1183 a<p>We have studied the shape resonance of excited states of sulphur dioxide (SO2) anion by using the correlated independent particle Fock space multi-reference coupled cluster (CAP-CIP-FSMRCCSD) method augmented by complex absorption potential. These resonant states have been trapped experimentally in recent years by electron collision. In particular, we have investigated e(-)-SO2 scattering and computed the negative-ion resonance states of the anion responsible for the two resonances around 4.45 and 6.56 eV and compared the results with the existing experimental observations. From the computational results using the CAP-CIP-FSMRCCSD method, it has been observed that both the resonances near 4.45 and 6.56 eV result from A(1) symmetries. [GRAPHICS] .</p>
10aCAP augmented correlated independent particle (CAP-CIP-FSMRCCSD)10acomplex absorption potential (CAP)10acoupled cluster10aFock space multireference coupled cluster (FSMRCCSD)10ashape resonance1 aBasumallick, Suhita1 aBhattacharya, Sumantra1 aJana, Irina1 aVaval, Nayana1 aPal, Sourav  uhttps://library.ncl.res.in/content/shape-resonance-sulphur-dioxide-anion-excited-states-using-cap-cip-fsmrccsd-method01585nas a2200253   4500008004100000022001400041245014100055210006900196260000800265300001100273490000800284520070400292653003200996653002201028653001601050653002701066653002001093653001501113100001601128700002401144700001601168700001801184856012901202       2021                        eng d  a0020-760800aResonance study: effect of partial triples excitation using complex absorbing potential-based Fock-space multi-reference coupled cluster0 aResonance study effect of partial triples excitation using compl  cSEP  ae267380 v1213 a<p>Resonances are metastable states with finite lifetime. They play important role in physics, chemistry and biology. The theoretical calculation of resonance state is a challenging problem. In this paper we have studied the shape resonance of Be, Mg, N-2 and CO. We have used correlated independent particle approximation to the Fock space multi-reference coupled cluster singles-doubles with third-order triples (CAP-CIP-FSMRCCSD(T)) method augmented by complex absorption potential. The resonance energy and decay widths are obtained by solving a non-Hermitian eigen-value problem within FSMRCC framework. The effects of the lowest order triples on the resonance energy and decay are studied.</p>10acomplex absorbing potential10aelectron affinity10aFock&\#820810anegative ion resonance10apartial triples10aspace MRCC1 aJana, Irina1 aBasumallick, Suhita1 aPal, Sourav1 aVaval, Nayana  uhttps://library.ncl.res.in/content/resonance-study-effect-partial-triples-excitation-using-complex-absorbing-potential-based