Vibrational spectroscopy microscopy and computational modelling

在我们的研究中，我们用一种叫做振动光谱学的技术，用可见光和红外光探测物质的组成。这项技术的原理是分子很像音叉。当叉子碰到像桌子这样的固体时，它会振动。分子要小得多；我们不是用桌子，而是用光线照射它们。如果波长合适，分子可以吸收能量并开始振动：化学键伸展、扭曲、摇摆等。每个分子都吸收一组独特的光能，这些光能随着分子中原子的数量和类型以及原子相互连接的方式而变化。我们从吸收的波长集（或振动谱）往回算，以获得有关分子结构的信息。我们可以研究的另一件事是被吸收的光的数量：有些振动比其他振动更容易开始。众所周知，这种差异取决于分子的结构；现在我们正试图找出导致某些振动不同于其他振动的具体因素。最先进的计算机建模与振动谱测量相结合。到目前为止，我们的研究集中在碳氢化合物分子上，也就是在石油和汽油中发现的那种物质，因为这些物质为我们提供了种类繁多的分子，它们都是由同样的两种基本元素构成的：碳和氢。这些分子在生物、石油化工和塑料工业等领域具有重要意义。我们获得的知识有许多潜在的应用，从更好地理解分子结构和分子之间的相互作用，到痕量大气气体的量化和生物医学研究。在这最后一个研究领域，生物物理光谱，我们记录和分析蛋白质的振动光谱，如在疤痕组织，骨骼和牙齿中发现的胶原蛋白。我们还使用这项技术来监测防晒霜和驱虫剂通过皮肤的渗透情况。最后，我们正在研究生长真菌的光谱，以在分子水平上更多地了解这些具有商业和环境重要性的物种。

In our research, we probe the composition of matter with visible and infrared light, using a technique called vibrational spectroscopy. This technique works on the principle that molecules are a lot like tuning forks. When struck against something solid, like a table, the fork vibrates. Molecules are a lot smaller; and instead of a table, we hit them with light. If the wavelength is just right, a molecule can absorb the energy and begin to vibrate: bonds stretch, twist, rock, etc. Each molecule absorbs a unique set of light energies, which vary with the number and type of atoms in a molecule, and with the ways in which the atoms are connected to each other. We work backward from the set (or vibrational spectrum) of wavelengths absorbed to get information about molecular structure. Another thing that we can investigate is the amount of light that is absorbed: some vibrations are easier to get started than others. The differences are known to depend on a molecule's structure; now we are trying to pinpoint the specific factors that make some vibrations different from others. State of the art computer modeling is combined with measurement of vibrational spectra. So far, we have concentrated our studies on hydrocarbon molecules, the sorts of things found in oil and gasoline, since these provide us with a vast variety of molecules, all constructed from the same two building blocks: carbon and hydrogen. These molecules are of great importance in fields such as biology, petrochemicals and the plastics industry. The knowledge that we gain has many potential applications, from a better understanding of molecular structure and interactions between molecules, to quantification of trace atmospheric gases and biomedical studies. In this last area of research, biophysical spectroscopy, we record and analyze the vibrational spectra of proteins, such as collagen found in scar tissue, bone and teeth. We also are using the technique to monitor penetration of sunscreen and insect repellent through skin. Finally, we are looking at the spectra of growing fungi, to learn more about these commercially and environmentally important species, at the molecular level.