Monte‐carlo‐rechnungen an makromolekülmodellen. 2. Mitt.: Quadratischer mittelwert des trägheitsradius und expansionskoeffizient

Bruns, Von Wolfgang

doi:10.1002/macp.1970.021340117

Cited by 10 publications

(1 citation statement)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Usually the chains that have been considered are constrained to lattices [1,2], although some studies on off-lattice chains have also been made recently [3][4][5]. Some important conclusions derived from such studies are [2]: (a) for long chains, the mean-square end-to-end distance, (r2), and the radius of gyration, ($2), are adequately expressible in terms of chain length by the following empirical relationships The inference of the properties of a polymer molecule from such investigations is based upon the presumption of a close correspondence between these rather naive model chains and real molecules.…”

Section: Introductionmentioning

confidence: 99%

‘Monte Carlo’ computer simulation of chain molecules III. Simulation ofn-alkane molecules

Lal

Spencer

1971

Molecular Physics

View full text Add to dashboard Cite

Considering a realistic model for isolated n-alkane molecules, their configurational behaviour has been explored employing a 'Monte Carlo' method. The present study shows that the behaviour of the short molecules is unlike that of the longer molecules in regard to the variation with temperature of the mean-square end-to-end distance and radius of gyration. For the short molecules the mean-square end-to-end distance and the radius of gyration are decreasing functions of temperature, but they increase with temperature in the case of the longer molecules. The macromolecules assume random-walk behaviour at approximately 600 K. The computed heat capacity versus temperature curves disclose configurational transitions in the chains.

show abstract

Section: Introductionmentioning

confidence: 99%

‘Monte Carlo’ computer simulation of chain molecules III. Simulation ofn-alkane molecules

Lal

Spencer

1971

Molecular Physics

View full text Add to dashboard Cite

show abstract

Monte‐Carlo‐rechnungen an makromolekülmodellen

Bruns

1972

Makromol. Chem.

View full text Add to dashboard Cite

ZUSAMMENFASSUNG:Fur zwei Perlenkettenmodelle im gitterfreien Raum wurden mit Hilfe von Monte-CarloMethoden unter Beriicksichtigung des ,,ausgeschlossenen Volumens" Zufallsketten bis zu einer Anzahl von etwa 100 Bauelementen erzeugt. Sie dienten zur Bestimmung der Verteilungsdichten des Fadenendenabstands (I), des Trlgheitsradius (11) und der Bauelemente um den Schwerpunkt (111). Dabei zeigte sich, d& die GAUSS sche Verteilung -besonders bei den llngeren Ketten -im Falle (I) und (111) eine brauchbare erste Naherung darstellt, wenn man mit den ,,experimentell" bestimmten quadratischen Mittelwerten rechnet. Nicht so befriedigend verlauft die analoge Anwendung der von FLORY fur ungestorte Ketten aufgestellten Verteilungsfunktion im Falle (11). Zur genaueren Beschreibung der Verteilungen wurde die Gleichung W(x)dx = C X E exp (-x/xn)tdx herangezogen und uber die reduzierten Momente die Parameter E und t bestimmt. Es wurde versucht. diese Werte auch fur sehr lange Ketten durch Extrapolation der reduzierten Momente zu ermitteln. Die willkurlich zu wahlende Extrapolationsmethode beeidul3t jedoch in gewissem MaDe die Ergebnisse. Sie konnen deshalb nicht als sehr zuverlassig angesehen werden. Dessenungeachtet befinden sie sich in grober Ubereinstimmung mit den Werten anderer Autoren, die diese fiir (I) fiir Gittermodelle ermittelt hatten. SUMMARY:Monte-Carlo-methods have been applied to generate non-intersecting random walks up to about 100 beads for two nonlattice necklace models. They were used to determine the distributions of the end-to-end distance (I), the radius of gyration (11), and the distances of the beads from the centre of gravity (111). The GAussian distribution was shown to be an acceptable first order approximation in case (I) and (111) especially for long chains, if the "experimentally" determined mean square values are taken into account. In case (11). however, the analogous application of the distribution function set up by FLORY for random chains, is not as satisfactory. To describe the distributions more exactly the equation W(x)dx = Cxe exp (-x/xn)tdx was used, and the parameters E and t were calculated by means of the reduced.moments of the distributions. The evaluation of E and t for very long chains has been tried by extrapolation of the reduced moments. The arbitrariness of the method of extrapolation, however, influences the results to a certain extent. Therefore they cannot be considered as too reliable. Notwithstanding they are in a rough agreement with the results of other authors, obtained from lattice-models for case (I). Einleitung

show abstract

Über die Gestalt von Polymermolekülen

Bruns¹

1976

Kristallinität Und Fehlordnung: Charakterisierung Und Technologische Bedeutung

View full text Add to dashboard Cite

Monte‐carlo‐rechnungen an makromolekülmodellen. 2. Mitt.: Quadratischer mittelwert des trägheitsradius und expansionskoeffizient

Cited by 10 publications

References 36 publications

‘Monte Carlo’ computer simulation of chain molecules III. Simulation ofn-alkane molecules

‘Monte Carlo’ computer simulation of chain molecules III. Simulation ofn-alkane molecules

Monte‐Carlo‐rechnungen an makromolekülmodellen

Über die Gestalt von Polymermolekülen

Contact Info

Product

Resources

About