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<p>Hello,</p>
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<p>I need access to electron wave functions, so I am using pw_export.x. However, I am confused by 'ngw' and 'igwx' in the output xml file.</p>
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<p>This is my understanding:</p>
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<p>1. 'Wfc_grids' - 'Kpoint.1' - 'grid' contains all Fourier base functions. For example, the first one is '0 0 0', which means the first Fourier base function is exp(i*(0*g1+<span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">0*g2+<span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">0*g3</span></span>)).</p>
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<p>2. 'Eigenvectors' - 'Kpoint.1' - 'Wfc.1' contains all Fourier coefficients of the wave function of the first band of the first k point. For example, if the first number is '-2.760388199287167E-002,-6.506816021159129E-001', the corresponding coefficient is <span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">-2.760388199287167E-002+i*<span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">-6.506816021159129E-001</span></span></p>
<p><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><br>
</span></span></p>
<p><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">3.
'igwx' tag in <span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">'Eigenvectors' - 'Kpoint.1' - 'info' is the number of
Fourier base functions.</span></span></span></p>
<p><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><br>
</span></span></p>
<p><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">What
bothers me is that there is another number 'ngwx' which is different from 'igwx'. Also 'Wfc-grids' - 'Kpoint.1' - 'index' has 'igwx' numbers but the last number is 'ngwx'.</span></span></p>
<p><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><br>
</span></span></p>
<p><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">I
want to know what's the meaning of 'ngwx' and 'igwx' so that I can make sure I correctly read the wave functions.</span></span></p>
<p><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><br>
</span></span></p>
<p><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">Best!</span></span></p>
<p><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><br>
</span></span></p>
<p><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">Chong
Wang</span></span></p>
<p>Ph.D. Candidate</p>
<p>Institute of Advanced Study, Tsinghua University, 100084, Beijing</p>
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