A high pressure Raman study of 9-hydroxyphenalenone and pressure-induced phase transitions

Jayaraman, A; Kourouklis, GA; Haddon, RC

dc.contributor.author	Jayaraman, A	en
dc.contributor.author	Kourouklis, GA	en
dc.contributor.author	Haddon, RC	en
dc.date.accessioned	2014-03-01T01:39:11Z
dc.date.available	2014-03-01T01:39:11Z
dc.date.issued	1987	en
dc.identifier.issn	00219606	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/22600
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-0000468875&partnerID=40&md5=3437b5db0921b5c917551f640ffde197	en
dc.title	A high pressure Raman study of 9-hydroxyphenalenone and pressure-induced phase transitions	en
heal.type	journalArticle	en
heal.publicationDate	1987	en
heal.abstract	The pressure effect on 9-hydroxyphenalenone (9-HPLN) has been investigated using Raman scattering and optical absorption techniques in a diamond anvil cell up to 70 kbar hydrostatic pressure. A pressure-induced first-order phase transition occurs near 6 kbar and the Raman data shows that the transition is to the same phase that is obtained on cooling 9-HPLN below 255 K at ambient pressure. The phase boundary has a positive slope with dT/dP=7 K/kbar. The Raman data indicate that there may be another phase change near 50 kbar. A strong and sharp Raman frequency near 12 cm-1 is observed in all the phases up to the highest pressure investigated. The weak pressure dependence of this frequency and its presence up to the highest pressure suggests that it may be a molecular mode rather than an external mode frequency. The optical absorption associated with π-π* excitation exhibits a large red shift, as expected of an aromatic molecular crystal. © 1987 American Institute of Physics.	en
heal.journalName	The Journal of Chemical Physics	en
dc.identifier.volume	87	en
dc.identifier.issue	6	en
dc.identifier.spage	3587	en
dc.identifier.epage	3590	en