A measure of the non-Gaussian character of a quantum state

听力真题1

Part A

The following is an interview with Emma Richards, one of Britain' s most successful sailors and the

youngest person to complete the Around Alone Race in May 2003. As you listen, answer Questions 1 to 10

by circling TRUE or FALSE. You will hear the interview only once.

1、 Emma grew up in a family with a sailing tradition.

2、 Emma enj oys the sense of being free on the sea.

3、 Sailing on the west coast of Scotland is a peaceful experience because Emma has a good

knowledge of the area.

4、 Emma' s second cruise around New Zealand impressed her a great deal.

5、 Most of the time Emma did not feel lonely sailing on her own.

6 、 The worst thing that happened to Emma during the Around Alone race was that she broke one

leg.

7、 Replacing one of the ropes at the top of the mast gave Emma a very hard time.

量子化学波谱计算基本流程

英文回答：

Quantum chemical spectroscopy is a powerful tool used

to study the electronic structure and properties of

molecules. It involves the calculation and analysis of

various spectroscopic properties, such as electronic

transitions, vibrational frequencies, and rotational

constants.

The basic workflow of quantum chemical spectroscopy can

be divided into several steps. First, we need to choose an

appropriate quantum chemical method to describe the

electronic structure of the molecule. This can range from

simple methods like the Hartree-Fock (HF) method to more

sophisticated methods like density functional theory (DFT)

or coupled cluster (CC) theory.

Once the method is chosen, we need to specify the basis

set, which is a set of functions used to represent the molecular orbitals. The choice of basis set can

15.Zhu,X.K.,O'Nions,R.K.,Guo,Y.&Reynolds,B.C.SecularvariationofironisotopesinNorthAtlanticdeepwater.Science287,2000±2002(2000).16.Belshaw,N.S.,Zhu,X.K.,Guo,Y.&O'Nions,R.K.Highprecisionmeasurementofironisotopesbyplasmasourcemassspectrometry.Int.J.Mass.Spectrom.197,191±195(2000).17.Marechal,C.N.,Telouk,P.&AlbareÁde,F.Preciseanalysisofcopperandzincisotopiccompositionsbyplasma-sourcemassspectrometry.Chem.Geol.156,251±273(1999).18.Clayton,R.N.&Mayeda,T.K.Formationofureilitesbynebularprocesses.Geochim.Cosmochim.Acta52,1313±1318(1988).19.Clayton,R.N.&Mayeda,T.K.Oxygenisotopestudiesofachondrites.Geochim.Cosmochim.Acta60,1999±2017(1996).20.Clayton,R.N.Mayeda,T.K.,Goswami,J.N.&Olsen,E.J.Oxygenisotopestudiesofordinarychondrites.Geochim.Cosmochim.Acta55,2317±2337(1991).21.Volkening,J.&Papanastassiou,D.A.Ironisotopeanomaly.Astrophys.J.347,L43±L46(1989).22.Volkening,J.&Papanastassiou,D.A.Zincisotopeanomaly.Astrophys.J.358,L29±L32(1990).23.Birck,J.L.&Lugmair,G.W.NickelandchromiumisotopesinAllendeinclusions.EarthPlanet.Sci.Lett.90,131±143(1988).24.Rotaru,M.,Birck,J.L.&AlleÁgre,C.J.Cluetoearlysolarsystemhistoryfromchromiumisotopesincarbonaceouschondrites.Nature358,465±470(1992).25.Podosek,F.A.etal.ThoroughlyanomalouschromiuminOrgueil.Meteorit.Planet.Sci.32,617±627(1997).26.Niemeyer,S.&Lugmair,G.W.Titaniumisotopicanomaliesinmeteorites.Geochim.Cosmochim.Acta48,1401±1416(1984).27.Niemeyer,S.&Lugmair,G.W.UbiquitousisotopicanomaliesinTifromnormalAllendeinclusions.EarthPlanet.Sci.Lett.53,211±225(1981).28.Papanastassiou,D.A.ChromiumisotopicanomaliesintheAllendemeteorite.Astrophys.J.308,L27±L30(1986).AcknowledgementsWethankN.S.Belshawforassistancewithmassspectrometry;A.Galyfordiscussionsandforprovidingsolutionaliquotsofsomesamplesanalysed;G.TurnerandF.AlbareÁdeforcommentsonthemanuscript;andM.PriceforprovidingsamplesoftheMtandOUMseries.ThisworkwassupportedbytheNaturalEnvironmentResearchCouncil.CorrespondenceandrequestsformaterialsshouldbeaddressedtoX.K.Z.(e-mail:xiangz@).letterstonature

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Size-induced acoustic hardening and optic softening of

phonons in CdS, InP, CeO

2, SnO

2, and Si nanostructures

Chang Q Sun

Schl EEE, NTU, Singapore ecqsun@.sg; .sg/home/ecqsun/

It has been puzzling that the Raman optical modes shift to lower frequency (or termed

as optical mode softening) associated with creation of Raman acoustic modes that

shift to higher energy (or called as acoustic hardening) upon nanosolid formation and

size reduction. Understandings of the mechanism behind the size-induced acoustic

hardening and optic softening have been quite controversial. On the basis of the recent

bond order-length-strength (BOLS) correlation [Phys. Rev. B 69 045105 (2004)], we

show that the optical softening arises from atomic cohesive energy weakening of

surface atoms and the acoustic mode hardening is predominated by intergrain