000905426 001__ 905426 000905426 005__ 20220131120330.0 000905426 037__ $$aFZJ-2022-00667 000905426 1001_ $$0P:(DE-Juel1)176716$$aWuttig, Matthias$$b0$$eCorresponding author$$ufzj 000905426 1112_ $$a2021 Virtual MRS Spring Meeting$$cSeattle$$d2021-04-17 - 2021-04-23$$wUSA 000905426 245__ $$aMetavalent Bonding in Solids: Provocation or Promise? 000905426 260__ $$c2021 000905426 3367_ $$033$$2EndNote$$aConference Paper 000905426 3367_ $$2DataCite$$aOther 000905426 3367_ $$2BibTeX$$aINPROCEEDINGS 000905426 3367_ $$2DRIVER$$aconferenceObject 000905426 3367_ $$2ORCID$$aLECTURE_SPEECH 000905426 3367_ $$0PUB:(DE-HGF)6$$2PUB:(DE-HGF)$$aConference Presentation$$bconf$$mconf$$s1642491856_18034$$xInvited 000905426 520__ $$aScientists and practitioners have long dreamt of designing materials with novel properties. Yet, a hundred years after quantum mechanics lay the foundations for a systematic description of the properties of solids, it is still not possible to predict the best material in applications such as photovoltaics, superconductivity or thermoelectric energy conversion. This is a sign of the complexity of the problem, which is often exacerbated by the need to optimize conflicting material properties. Hence, one can ponder if design routes for materials can be devised. In recent years, the focus of our work has been on designing advanced functional materials with attractive opto-electronic properties, including phase change materials, thermoelectrics, photonic switches and materials for photovoltaics. These materials are typically discussed as unconventional semiconductors, often but not always, with appreciable charge transfer. Phase Change Materials have provided a special challenge for materials optimization. They possess a remarkable property portfolio, which includes the ability to rapidly switch between the amorphous and crystalline state. Surprisingly, in PCMs both states differ significantly in their properties. This material combination makes them very attractive for applications in rewriteable optical and electronic data storage, as well as photonic switches. In this talk, the unconventional material properties will be attributed to a unique bonding mechanism (metavalent bonding). Further evidence for this bonding mechanism comes from a quantum-chemical map, which separates the known strong bonding mechanisms of metallic, ionic and covalent bonding. The map reveals that metavalent bonding is a new, fundamental bonding mechanism, which differs substantially from metallic, covalent and ionic bonding. This insight is subsequently employed to design phase change as well as thermoelectric materials. Yet, the discoveries presented here also force us to revisit the concept of chemical bonds and bring back a history of vivid scientific disputes about ‘the nature of the chemical bond’. 000905426 536__ $$0G:(DE-HGF)POF4-5233$$a5233 - Memristive Materials and Devices (POF4-523)$$cPOF4-523$$fPOF IV$$x0 000905426 909CO $$ooai:juser.fz-juelich.de:905426$$pVDB 000905426 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)176716$$aForschungszentrum Jülich$$b0$$kFZJ 000905426 9131_ $$0G:(DE-HGF)POF4-523$$1G:(DE-HGF)POF4-520$$2G:(DE-HGF)POF4-500$$3G:(DE-HGF)POF4$$4G:(DE-HGF)POF$$9G:(DE-HGF)POF4-5233$$aDE-HGF$$bKey Technologies$$lNatural, Artificial and Cognitive Information Processing$$vNeuromorphic Computing and Network Dynamics$$x0 000905426 9141_ $$y2021 000905426 920__ $$lyes 000905426 9201_ $$0I:(DE-Juel1)PGI-10-20170113$$kPGI-10$$lJARA Institut Green IT$$x0 000905426 980__ $$aconf 000905426 980__ $$aVDB 000905426 980__ $$aI:(DE-Juel1)PGI-10-20170113 000905426 980__ $$aUNRESTRICTED