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Journal of the Korean Chemical Society (JKCS)

ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 8, Number 2
April 20, 1964 

Significant Structure of Liquid Water

물의 구조와 성질
Hyungsuk Pak, Seihun Chang

박형석, 장세헌
물은 용융점, 끊는점, 용융열 및 증발열등의 수소와 6족원소와의 화합물의 성질로부터 예측되는 값보다 훨씬 크고, ice-I녹을 때 부피의 감소가 일어나는 등 특이한 성질을 가지고 있다. 이와같은 성질들을 정략적으로 설명하려고 지금까지 많은 연구자들이 노력해왔다. 저자들은 물의 큰 표면자유에네르기와 용융시의 특수한 부피변화로 미루어 물의 구조모델을 다음과 같이 생각하였다. 즉, 얼음이 용융함에 따라 분자크기의 이동성 빈자리가 도입되면 물의 큰 표면에네르기 밀도로 말미암아 빈자리 주위의 물분자는 촘촘한 배열을 가지게 되면 빈자리에서 떨어져있는 분자는 ice-I의 구조를 자질것으로 생각된다. 빈자리 주위의 분자가 빈자리에 뛰어 들어갈 때는 이동자유도를 지니게 될 것이다. 저자들은 H. Eyring의 액체구조이론을 써서 물의 liquid partition function을 위에 말한 바와 같이 구조모델로부터 유도하고 물의 증기압, 용융 및 증발엔트로피 등 여러가지 열역학적 성질 및 몰부피를 계산하여 실측치와 좋은 일치를 얻었다.

Water has the melting point, the boiling point, the heat of fusion, and the heat of vaporization all much higher than would be normally expected from the hydrogen compounds of the other members of the oxygen family. Another unique characteristic of ice-Ⅰ is its volume decrease which takes place in its melting. A number of significant efforts have been made in the past to explain these properties quantitatively. The authors, reasoning from the unusually great free surface energy of water and the characteristic volume change on melting, propose the structural model of liquid water as follows. On melting, fluidized vacancies of a molecular size are introduced. Thereupon, for the unusually great surface energy density, molecules surrounding the vacancies become to have close packed arrangement. But molecules not in direct contact with vacancies should still possess the original structure i. e., ice-Ⅰ. When a molecule adjacent to a vacancy jumps into the vacancy, the It was confirmed that korean scabby barley during the summer of 1963 was infected with Gibberella zeae. Feeding experiments showed that the diseased grain was toxic and induced emesis in pigs. The concentrated extracts which contained the emetic principle were prepared by refluxing the grain with methanol or water for 5 hours and then concentrating the filtrates and the washing in vacuum. Animal tests proved that methanol extraction for the emetic principle was more effective than extraction with water.

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