Phase behavior and polymorphism of organic crystals confined within nanoscale chambers

Jeong Myeong Ha, Benjamin D. Hamilton, Marc A. Hillmyer, Michael Ward

Research output: Contribution to journalArticle

Abstract

Controlling polymorphism, the ability of a compound to adopt more than one solid-state structure, often relies on empirical manipulations of conditions such as solvent, temperature, and mode of crystallization. Despite a growing interest in nanocrystalline formulations, however, the influence of crystal size on polymorph formation and stability is largely unexplored. Nanocrystals of pimelic acid, HO2C(CH2)n-2 CO2H (n = 7), glutaric acid (n = 5), suberic acid (n = 8), and coumarin (1, 2-benzopyrone) in nanometer-scale pores of controlled pore glass (CPG) beads and hexagonally ordered cylindrical pores of poly(cyclohexylethylene) (p-PCHE) monoliths exhibit size-dependent polymorphism and thermotropic behavior because of the physical constraints imposed by the dimensions of the pores. Pimelic acid, suberic acid, and coumarin also exhibit heretofore unknown polymorphs, denoted δ-pimelic acid, β-suberic acid, and β-coumarin, in CPG with pore sizes < 23 nm and p-PCHE with pore diameters < 40 nm. The melting points of the confined crystals decrease monotonically with decreasing pore size, and the enantiotropic phase behavior of bulk glutaric acid and suberic acid switches to monotropic when confined within the nanoscale pores of CPG and p-PCHE. Collectively, these results reveal that nanometer-scale size confinement can alter crystallization outcomes and affect polymorph stability compared with bulk crystallization. Moreover, crystallization in very small pores can lead to the discovery of new polymorphs that otherwise would not be detected using conventional screening methods.

Original languageEnglish (US)
Pages (from-to)4766-4777
Number of pages12
JournalCrystal Growth and Design
Volume9
Issue number11
DOIs
StatePublished - Nov 4 2009

Fingerprint

polymorphism
Phase behavior
Polymorphism
Pimelic Acids
chambers
Crystallization
porosity
Crystals
Acids
acids
crystals
Glass
Pore size
crystallization
glass
Nanocrystals
Melting point
Screening
Switches
coumarin

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics

Cite this

Phase behavior and polymorphism of organic crystals confined within nanoscale chambers. / Ha, Jeong Myeong; Hamilton, Benjamin D.; Hillmyer, Marc A.; Ward, Michael.

In: Crystal Growth and Design, Vol. 9, No. 11, 04.11.2009, p. 4766-4777.

Research output: Contribution to journalArticle

Ha, Jeong Myeong ; Hamilton, Benjamin D. ; Hillmyer, Marc A. ; Ward, Michael. / Phase behavior and polymorphism of organic crystals confined within nanoscale chambers. In: Crystal Growth and Design. 2009 ; Vol. 9, No. 11. pp. 4766-4777.
@article{261db95e2bf4479cb84fd49f60ad4ece,
title = "Phase behavior and polymorphism of organic crystals confined within nanoscale chambers",
abstract = "Controlling polymorphism, the ability of a compound to adopt more than one solid-state structure, often relies on empirical manipulations of conditions such as solvent, temperature, and mode of crystallization. Despite a growing interest in nanocrystalline formulations, however, the influence of crystal size on polymorph formation and stability is largely unexplored. Nanocrystals of pimelic acid, HO2C(CH2)n-2 CO2H (n = 7), glutaric acid (n = 5), suberic acid (n = 8), and coumarin (1, 2-benzopyrone) in nanometer-scale pores of controlled pore glass (CPG) beads and hexagonally ordered cylindrical pores of poly(cyclohexylethylene) (p-PCHE) monoliths exhibit size-dependent polymorphism and thermotropic behavior because of the physical constraints imposed by the dimensions of the pores. Pimelic acid, suberic acid, and coumarin also exhibit heretofore unknown polymorphs, denoted δ-pimelic acid, β-suberic acid, and β-coumarin, in CPG with pore sizes < 23 nm and p-PCHE with pore diameters < 40 nm. The melting points of the confined crystals decrease monotonically with decreasing pore size, and the enantiotropic phase behavior of bulk glutaric acid and suberic acid switches to monotropic when confined within the nanoscale pores of CPG and p-PCHE. Collectively, these results reveal that nanometer-scale size confinement can alter crystallization outcomes and affect polymorph stability compared with bulk crystallization. Moreover, crystallization in very small pores can lead to the discovery of new polymorphs that otherwise would not be detected using conventional screening methods.",
author = "Ha, {Jeong Myeong} and Hamilton, {Benjamin D.} and Hillmyer, {Marc A.} and Michael Ward",
year = "2009",
month = "11",
day = "4",
doi = "10.1021/cg9006185",
language = "English (US)",
volume = "9",
pages = "4766--4777",
journal = "Crystal Growth and Design",
issn = "1528-7483",
publisher = "American Chemical Society",
number = "11",

}

TY - JOUR

T1 - Phase behavior and polymorphism of organic crystals confined within nanoscale chambers

AU - Ha, Jeong Myeong

AU - Hamilton, Benjamin D.

AU - Hillmyer, Marc A.

AU - Ward, Michael

PY - 2009/11/4

Y1 - 2009/11/4

N2 - Controlling polymorphism, the ability of a compound to adopt more than one solid-state structure, often relies on empirical manipulations of conditions such as solvent, temperature, and mode of crystallization. Despite a growing interest in nanocrystalline formulations, however, the influence of crystal size on polymorph formation and stability is largely unexplored. Nanocrystals of pimelic acid, HO2C(CH2)n-2 CO2H (n = 7), glutaric acid (n = 5), suberic acid (n = 8), and coumarin (1, 2-benzopyrone) in nanometer-scale pores of controlled pore glass (CPG) beads and hexagonally ordered cylindrical pores of poly(cyclohexylethylene) (p-PCHE) monoliths exhibit size-dependent polymorphism and thermotropic behavior because of the physical constraints imposed by the dimensions of the pores. Pimelic acid, suberic acid, and coumarin also exhibit heretofore unknown polymorphs, denoted δ-pimelic acid, β-suberic acid, and β-coumarin, in CPG with pore sizes < 23 nm and p-PCHE with pore diameters < 40 nm. The melting points of the confined crystals decrease monotonically with decreasing pore size, and the enantiotropic phase behavior of bulk glutaric acid and suberic acid switches to monotropic when confined within the nanoscale pores of CPG and p-PCHE. Collectively, these results reveal that nanometer-scale size confinement can alter crystallization outcomes and affect polymorph stability compared with bulk crystallization. Moreover, crystallization in very small pores can lead to the discovery of new polymorphs that otherwise would not be detected using conventional screening methods.

AB - Controlling polymorphism, the ability of a compound to adopt more than one solid-state structure, often relies on empirical manipulations of conditions such as solvent, temperature, and mode of crystallization. Despite a growing interest in nanocrystalline formulations, however, the influence of crystal size on polymorph formation and stability is largely unexplored. Nanocrystals of pimelic acid, HO2C(CH2)n-2 CO2H (n = 7), glutaric acid (n = 5), suberic acid (n = 8), and coumarin (1, 2-benzopyrone) in nanometer-scale pores of controlled pore glass (CPG) beads and hexagonally ordered cylindrical pores of poly(cyclohexylethylene) (p-PCHE) monoliths exhibit size-dependent polymorphism and thermotropic behavior because of the physical constraints imposed by the dimensions of the pores. Pimelic acid, suberic acid, and coumarin also exhibit heretofore unknown polymorphs, denoted δ-pimelic acid, β-suberic acid, and β-coumarin, in CPG with pore sizes < 23 nm and p-PCHE with pore diameters < 40 nm. The melting points of the confined crystals decrease monotonically with decreasing pore size, and the enantiotropic phase behavior of bulk glutaric acid and suberic acid switches to monotropic when confined within the nanoscale pores of CPG and p-PCHE. Collectively, these results reveal that nanometer-scale size confinement can alter crystallization outcomes and affect polymorph stability compared with bulk crystallization. Moreover, crystallization in very small pores can lead to the discovery of new polymorphs that otherwise would not be detected using conventional screening methods.

UR - http://www.scopus.com/inward/record.url?scp=72949103658&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=72949103658&partnerID=8YFLogxK

U2 - 10.1021/cg9006185

DO - 10.1021/cg9006185

M3 - Article

VL - 9

SP - 4766

EP - 4777

JO - Crystal Growth and Design

JF - Crystal Growth and Design

SN - 1528-7483

IS - 11

ER -