異核去偶是固態NMR取得高解析度至關重要的方法。目前已有許多異核去偶方法被開發出來，諸如TPPM，XiX，SPINAL，以及近年來的對稱型脈衝序列和eDROOPY等。然而，這些序列大多是針對自由演化和長方脈衝期間的體系進行去偶，並不考慮自旋體系的即時狀態。而在形狀化脈衝期間，去偶脈衝對演化及去偶效果的影響和最佳化，據我們所知，還未有人系統性地研究過。
本研究嘗試由形狀化重聚脈衝著手，試圖在脈衝期間，進行形狀化的去偶。我們選擇了r-SNOB和Gaussian等常用的選形重聚脈衝，並在重聚脈衝期間，分別以連續波，長脈衝，TPPM，Gaussian和Sinc等脈衝進行去偶。從我們所獲得的光譜中，發現了一些過去從未在固態NMR中發現的新現象。我們的研究結果顯示，若選形重聚脈衝期間，功率未達閾值，即將所有訊號消除。另外許多選形脈衝具有顯著去相的效果。本研究初步驗證了形狀脈衝期間的去偶的圖像，和自旋回波整體的去偶，在自旋演化上是存在差異的。

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目錄
1. 緒論……………………………………………………………………………………………….1
第一部份：背景與原理
2. 固態NMR異核去偶評述……………………………………………………………….4
2.1 異核偶極偶合……………………………………………………………………………….4
2.2 異核去偶概論……………………………………………………………………………….5
2.3 異核去偶方法……………………………………………………………………………….8
2.4 對稱理論與異核去偶探討…………………………………………………...………...12
2.4.1 座標變換……………………………………………………………………………...12
2.4.2 射頻Euler角.............................................................................................16
2.4.3 對稱類型...................................................................................................17
2.4.4 平均Hamiltonian理論和對稱選擇律.....................................................21
2.4.5 對稱選擇律與異核去偶...........................................................................24
3. 選擇性形狀脈衝概論.........................................................................29
3.1 緒論..................................................................................................................29
3.2 基本原理..........................................................................................................31
第二部分：實驗
4. 實驗.....................................................................................................35
4.1 實驗設計..........................................................................................................35
4.2 儀器簡介......................................................................................................... 35
4.3 脈衝序列及參數..............................................................................................36
4.3.1 CP/MAS 實驗...........................................................................................36
4.3.2 重聚脈衝序列.......................................................................................... 37
5. 結果，討論，結論與展望..................................................................40
5.1 實驗結果..........................................................................................................40
5.2 結果討論..........................................................................................................57
5.3 結論..................................................................................................................58
5.4 展望..................................................................................................................59

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