Balmes Olivier, Malm Jan-Olle, Pettersson Niklas, Karlsson Gunnel, Bovin Jan-Olov
National Center for High Resolution Electron Microscopy, Department of Materials Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
Microsc Microanal. 2006 Apr;12(2):145-50. doi: 10.1017/S1431927606060119.
It has been shown, by imaging gold (200) planes, that it is possible to achieve better than 0.20-nm structural resolution in cryo-transmission electron microscopy (cryo-TEM). This has been done using commercially available cryo equipment and using a 300-kV field emission gun (FEG) TEM. The images of 15-nm gold particles embedded in amorphous frozen water clearly show the (111) planes (separated by 0.235 nm) in gold. Fourier transform demonstrates the presence of (200) planes in the image, proving a resolution of better than 0.20 nm. The experimental results are supported by image simulations using the multislice method. These simulations suggest that it should be possible to achieve the same resolution even in smaller particles and particles of lighter elements. The crucial experimental problem to overcome is keeping the thickness of the amorphous film low and to work at low electron dose conditions.
通过对金（200）平面成像表明，在低温透射电子显微镜（cryo-TEM）中可以实现优于0.20纳米的结构分辨率。这是使用市售的低温设备和300 kV场发射枪（FEG）TEM完成的。嵌入非晶态冷冻水中的15纳米金颗粒的图像清楚地显示了金中的（111）平面（间距为0.235纳米）。傅里叶变换证明图像中存在（200）平面，证明分辨率优于0.20纳米。实验结果得到了使用多层法的图像模拟结果的支持。这些模拟表明，即使在更小的颗粒和更轻元素的颗粒中也应该能够实现相同的分辨率。要克服的关键实验问题是保持非晶膜的厚度较低，并在低电子剂量条件下工作。
